| blob | 6597111955e945b02862cda4c433a9bf1eb96b78 |
1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
12 any later version.
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
24 /* High-level class interface. */
41 /* The number of nested classes being processed. If we are not in the
42 scope of any class, this is zero. */
46 /* In order to deal with nested classes, we keep a stack of classes.
47 The topmost entry is the innermost class, and is the entry at index
48 CURRENT_CLASS_DEPTH */
51 /* The name of the class. */
52 tree name;
54 /* The _TYPE node for the class. */
55 tree type;
57 /* The access specifier pending for new declarations in the scope of
58 this class. */
59 tree access;
61 /* If were defining TYPE, the names used in this class. */
62 splay_tree names_used;
64 /* Nonzero if this class is no longer open, because of a call to
65 push_to_top_level. */
70 {
71 /* The base for which we're building initializers. */
72 tree binfo;
73 /* The type of the most-derived type. */
74 tree derived;
75 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
76 unless ctor_vtbl_p is true. */
77 tree rtti_binfo;
78 /* The negative-index vtable initializers built up so far. These
79 are in order from least negative index to most negative index. */
81 /* The binfo for the virtual base for which we're building
82 vcall offset initializers. */
83 tree vbase;
84 /* The functions in vbase for which we have already provided vcall
85 offsets. */
87 /* The vtable index of the next vcall or vbase offset. */
88 tree index;
89 /* Nonzero if we are building the initializer for the primary
90 vtable. */
92 /* Nonzero if we are building the initializer for a construction
93 vtable. */
95 /* True when adding vcall offset entries to the vtable. False when
96 merely computing the indices. */
100 /* The type of a function passed to walk_subobject_offsets. */
103 /* The stack itself. This is a dynamically resized array. The
104 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
108 /* The size of the largest empty class seen in this translation unit. */
111 /* An array of all local classes present in this translation unit, in
112 declaration order. */
202 splay_tree_key k2);
211 /* Variables shared between class.c and call.c. */
213 #ifdef GATHER_STATISTICS
221 #endif
223 /* Convert to or from a base subobject. EXPR is an expression of type
224 `A' or `A*', an expression of type `B' or `B*' is returned. To
225 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
226 the B base instance within A. To convert base A to derived B, CODE
227 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
228 In this latter case, A must not be a morally virtual base of B.
229 NONNULL is true if EXPR is known to be non-NULL (this is only
230 needed when EXPR is of pointer type). CV qualifiers are preserved
231 from EXPR. */
233 tree
235 tree expr,
236 tree binfo,
238 {
241 tree probe;
242 tree offset;
243 tree target_type;
245 tree ptr_target_type;
255 {
261 }
273 /* Nothing to do. */
277 {
281 }
284 /* This must happen before the call to save_expr. */
286 else
293 /* Do we need to look in the vtable for the real offset? */
296 /* Don't bother with the calculations inside sizeof; they'll ICE if the
297 source type is incomplete and the pointer value doesn't matter. */
299 {
304 }
306 /* Do we need to check for a null pointer? */
308 {
309 /* If we know the conversion will not actually change the value
310 of EXPR, then we can avoid testing the expression for NULL.
311 We have to avoid generating a COMPONENT_REF for a base class
312 field, because other parts of the compiler know that such
313 expressions are always non-NULL. */
315 {
316 tree class_type;
317 /* TARGET_TYPE has been extracted from BINFO, and, is
318 therefore always cv-unqualified. Extract the
319 cv-qualifiers from EXPR so that the expression returned
320 matches the input. */
322 target_type
326 }
328 }
330 /* Protect against multiple evaluation if necessary. */
334 /* Now that we've saved expr, build the real null test. */
336 {
340 }
342 /* If this is a simple base reference, express it as a COMPONENT_REF. */
344 /* We don't build base fields for empty bases, and they aren't very
345 interesting to the optimizers anyway. */
347 {
354 }
357 {
358 /* Going via virtual base V_BINFO. We need the static offset
359 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
360 V_BINFO. That offset is an entry in D_BINFO's vtable. */
361 tree v_offset;
364 {
365 /* In a base member initializer, we cannot rely on the
366 vtable being set up. We have to indirect via the
367 vtt_parm. */
368 tree t;
374 tf_warning_or_error);
375 }
376 else
378 tf_warning_or_error),
385 v_offset);
397 /* Negative fixed_type_p means this is a constructor or destructor;
398 virtual base layout is fixed in in-charge [cd]tors, but not in
399 base [cd]tors. */
403 v_offset,
406 else
408 }
410 target_type = cp_build_qualified_type
419 {
424 }
425 else
431 out:
435 integer_zero_node));
438 }
440 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
441 Perform a derived-to-base conversion by recursively building up a
442 sequence of COMPONENT_REFs to the appropriate base fields. */
444 static tree
446 {
449 tree field;
452 {
453 tree temp;
457 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
458 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
459 an lvalue in the front end; only _DECLs and _REFs are lvalues
460 in the back end. */
466 }
468 /* Recurse. */
473 /* Is this the base field created by build_base_field? */
477 {
478 /* We don't use build_class_member_access_expr here, as that
479 has unnecessary checks, and more importantly results in
480 recursive calls to dfs_walk_once. */
488 /* Mark the expression const or volatile, as appropriate.
489 Even though we've dealt with the type above, we still have
490 to mark the expression itself. */
497 }
499 /* Didn't find the base field?!? */
501 }
503 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
504 type is a class type or a pointer to a class type. In the former
505 case, TYPE is also a class type; in the latter it is another
506 pointer type. If CHECK_ACCESS is true, an error message is emitted
507 if TYPE is inaccessible. If OBJECT has pointer type, the value is
508 assumed to be non-NULL. */
510 tree
512 tsubst_flags_t complain)
513 {
514 tree binfo;
515 tree object_type;
516 base_access access;
519 {
522 }
523 else
530 access,
531 NULL);
536 }
538 /* EXPR is an expression with unqualified class type. BASE is a base
539 binfo of that class type. Returns EXPR, converted to the BASE
540 type. This function assumes that EXPR is the most derived class;
541 therefore virtual bases can be found at their static offsets. */
543 tree
545 {
546 tree expr_type;
550 {
551 tree pointer_type;
555 /* We use fold_build2 and fold_convert below to simplify the trees
556 provided to the optimizers. It is not safe to call these functions
557 when processing a template because they do not handle C++-specific
558 trees. */
561 tf_warning_or_error);
568 }
571 }
573 \f
574 tree
576 {
582 /* First, convert to the requested type. */
587 /* Second, the requested type may not be the owner of its own vptr.
588 If not, convert to the base class that owns it. We cannot use
589 convert_to_base here, because VCONTEXT may appear more than once
590 in the inheritance hierarchy of TYPE, and thus direct conversion
591 between the types may be ambiguous. Following the path back up
592 one step at a time via primary bases avoids the problem. */
596 {
599 }
602 }
604 /* Given an object INSTANCE, return an expression which yields the
605 vtable element corresponding to INDEX. There are many special
606 cases for INSTANCE which we take care of here, mainly to avoid
607 creating extra tree nodes when we don't have to. */
609 static tree
611 {
612 tree aref;
615 /* Try to figure out what a reference refers to, and
616 access its virtual function table directly. */
624 {
629 }
638 }
640 tree
642 {
646 }
648 /* Given a stable object pointer INSTANCE_PTR, return an expression which
649 yields a function pointer corresponding to vtable element INDEX. */
651 tree
653 {
654 tree aref;
657 tf_warning_or_error),
658 idx);
660 /* When using function descriptors, the address of the
661 vtable entry is treated as a function pointer. */
665 tf_warning_or_error));
667 /* Remember this as a method reference, for later devirtualization. */
671 }
673 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
674 for the given TYPE. */
676 static tree
678 {
680 }
682 /* DECL is an entity associated with TYPE, like a virtual table or an
683 implicitly generated constructor. Determine whether or not DECL
684 should have external or internal linkage at the object file
685 level. This routine does not deal with COMDAT linkage and other
686 similar complexities; it simply sets TREE_PUBLIC if it possible for
687 entities in other translation units to contain copies of DECL, in
688 the abstract. */
690 void
692 {
693 /* If TYPE involves a local class in a function with internal
694 linkage, then DECL should have internal linkage too. Other local
695 classes have no linkage -- but if their containing functions
696 have external linkage, it makes sense for DECL to have external
697 linkage too. That will allow template definitions to be merged,
698 for example. */
700 {
703 }
704 else
706 }
708 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
709 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
710 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
712 static tree
714 {
715 tree decl;
718 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
719 now to avoid confusion in mangle_decl. */
728 /* At one time the vtable info was grabbed 2 words at a time. This
729 fails on sparc unless you have 8-byte alignment. (tiemann) */
733 /* The vtable has not been defined -- yet. */
737 /* Mark the VAR_DECL node representing the vtable itself as a
738 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
739 is rather important that such things be ignored because any
740 effort to actually generate DWARF for them will run into
741 trouble when/if we encounter code like:
743 #pragma interface
744 struct S { virtual void member (); };
746 because the artificial declaration of the vtable itself (as
747 manufactured by the g++ front end) will say that the vtable is
748 a static member of `S' but only *after* the debug output for
749 the definition of `S' has already been output. This causes
750 grief because the DWARF entry for the definition of the vtable
751 will try to refer back to an earlier *declaration* of the
752 vtable as a static member of `S' and there won't be one. We
753 might be able to arrange to have the "vtable static member"
754 attached to the member list for `S' before the debug info for
755 `S' get written (which would solve the problem) but that would
756 require more intrusive changes to the g++ front end. */
760 }
762 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
763 or even complete. If this does not exist, create it. If COMPLETE is
764 nonzero, then complete the definition of it -- that will render it
765 impossible to actually build the vtable, but is useful to get at those
766 which are known to exist in the runtime. */
768 tree
770 {
771 tree decl;
780 {
783 }
786 }
788 /* Build the primary virtual function table for TYPE. If BINFO is
789 non-NULL, build the vtable starting with the initial approximation
790 that it is the same as the one which is the head of the association
791 list. Returns a nonzero value if a new vtable is actually
792 created. */
794 static int
796 {
797 tree decl;
798 tree virtuals;
803 {
805 /* We have already created a vtable for this base, so there's
806 no need to do it again. */
813 }
814 else
815 {
818 }
820 #ifdef GATHER_STATISTICS
823 #endif
825 /* Initialize the association list for this type, based
826 on our first approximation. */
831 }
833 /* Give BINFO a new virtual function table which is initialized
834 with a skeleton-copy of its original initialization. The only
835 entry that changes is the `delta' entry, so we can really
836 share a lot of structure.
838 FOR_TYPE is the most derived type which caused this table to
839 be needed.
841 Returns nonzero if we haven't met BINFO before.
843 The order in which vtables are built (by calling this function) for
844 an object must remain the same, otherwise a binary incompatibility
845 can result. */
847 static int
849 {
851 /* We already created a vtable for this base. There's no need to
852 do it again. */
855 /* Remember that we've created a vtable for this BINFO, so that we
856 don't try to do so again. */
859 /* Make fresh virtual list, so we can smash it later. */
862 /* Secondary vtables are laid out as part of the same structure as
863 the primary vtable. */
866 }
868 /* Create a new vtable for BINFO which is the hierarchy dominated by
869 T. Return nonzero if we actually created a new vtable. */
871 static int
873 {
875 /* In this case, it is *type*'s vtable we are modifying. We start
876 with the approximation that its vtable is that of the
877 immediate base class. */
879 else
880 /* This is our very own copy of `basetype' to play with. Later,
881 we will fill in all the virtual functions that override the
882 virtual functions in these base classes which are not defined
883 by the current type. */
885 }
887 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
888 (which is in the hierarchy dominated by T) list FNDECL as its
889 BV_FN. DELTA is the required constant adjustment from the `this'
890 pointer where the vtable entry appears to the `this' required when
891 the function is actually called. */
893 static void
895 tree binfo,
896 tree fndecl,
897 tree delta,
899 {
900 tree v;
906 {
907 /* We need a new vtable for BINFO. */
909 {
910 /* If we really did make a new vtable, we also made a copy
911 of the BINFO_VIRTUALS list. Now, we have to find the
912 corresponding entry in that list. */
917 }
922 }
923 }
925 \f
926 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
927 the USING_DECL naming METHOD. Returns true if the method could be
928 added to the method vec. */
930 bool
932 {
934 tree overload;
940 tree current_fns;
941 tree fns;
954 {
955 /* Make a new method vector. We start with 8 entries. We must
956 allocate at least two (for constructors and destructors), and
957 we're going to end up with an assignment operator at some
958 point as well. */
960 /* Create slots for constructors and destructors. */
964 }
966 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
969 /* Constructors and destructors go in special slots. */
973 {
977 {
983 type);
984 }
985 }
986 else
987 {
988 tree m;
991 /* See if we already have an entry with this name. */
995 {
998 {
1003 }
1007 {
1010 }
1015 }
1016 }
1019 /* Check to see if we've already got this method. */
1021 {
1023 tree fn_type;
1024 tree method_type;
1025 tree parms1;
1026 tree parms2;
1031 /* [over.load] Member function declarations with the
1032 same name and the same parameter types cannot be
1033 overloaded if any of them is a static member
1034 function declaration.
1036 [namespace.udecl] When a using-declaration brings names
1037 from a base class into a derived class scope, member
1038 functions in the derived class override and/or hide member
1039 functions with the same name and parameter types in a base
1040 class (rather than conflicting). */
1046 /* Compare the quals on the 'this' parm. Don't compare
1047 the whole types, as used functions are treated as
1048 coming from the using class in overload resolution. */
1057 /* For templates, the return type and template parameters
1058 must be identical. */
1075 {
1077 {
1079 /* Defer to the local function. */
1083 else
1085 using_decl);
1086 }
1087 else
1088 {
1091 }
1093 /* We don't call duplicate_decls here to merge the
1094 declarations because that will confuse things if the
1095 methods have inline definitions. In particular, we
1096 will crash while processing the definitions. */
1098 }
1099 }
1101 /* A class should never have more than one destructor. */
1105 /* Add the new binding. */
1114 {
1117 /* We only expect to add few methods in the COMPLETE_P case, so
1118 just make room for one more method in that case. */
1121 else
1127 else
1129 }
1130 else
1131 /* Replace the current slot. */
1134 }
1136 /* Subroutines of finish_struct. */
1138 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1139 legit, otherwise return 0. */
1141 static int
1143 {
1144 tree elem;
1153 {
1155 {
1159 else
1162 }
1163 else
1164 {
1165 /* They're changing the access to the same thing they changed
1166 it to before. That's OK. */
1167 ;
1168 }
1169 }
1170 else
1171 {
1175 }
1177 }
1179 /* Process the USING_DECL, which is a member of T. */
1181 static void
1183 {
1186 tree access
1191 tree old_value;
1197 {
1203 else
1205 }
1213 ;
1215 {
1217 /* It's OK to use functions from a base when there are functions with
1219 else
1220 {
1225 }
1226 }
1228 {
1232 }
1234 /* Make type T see field decl FDECL with access ACCESS. */
1237 {
1240 }
1241 else
1243 }
1244 \f
1245 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1246 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1247 properties of the bases. */
1249 static void
1253 {
1256 tree base_binfo;
1257 tree binfo;
1269 {
1274 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1275 here because the case of virtual functions but non-virtual
1276 dtor is handled in finish_struct_1. */
1281 /* If the base class doesn't have copy constructors or
1282 assignment operators that take const references, then the
1283 derived class cannot have such a member automatically
1284 generated. */
1293 /* A virtual base does not effect nearly emptiness. */
1294 ;
1296 {
1298 /* And if there is more than one nearly empty base, then the
1299 derived class is not nearly empty either. */
1301 else
1302 /* Remember we've seen one. */
1304 }
1306 /* If the base class is not empty or nearly empty, then this
1307 class cannot be nearly empty. */
1310 /* A lot of properties from the bases also apply to the derived
1311 class. */
1329 /* A standard-layout class is a class that:
1330 ...
1331 * has no non-standard-layout base classes, */
1334 {
1335 tree basefield;
1336 /* ...has no base classes of the same type as the first non-static
1337 data member... */
1339 && (same_type_ignoring_top_level_qualifiers_p
1342 else
1343 /* ...either has no non-static data members in the most-derived
1344 class and at most one base class with non-static data
1345 members, or has no base classes with non-static data
1346 members */
1350 {
1353 else
1356 }
1357 }
1358 }
1359 }
1361 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1362 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1363 that have had a nearly-empty virtual primary base stolen by some
1364 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1365 T. */
1367 static void
1369 {
1373 tree base_binfo;
1375 /* Determine the primary bases of our bases. */
1378 {
1381 /* See if we're the non-virtual primary of our inheritance
1382 chain. */
1384 {
1391 /* We are the primary binfo. */
1393 }
1394 /* Determine if we have a virtual primary base, and mark it so.
1395 */
1397 {
1401 /* Someone already claimed this base. */
1403 else
1404 {
1405 tree delta;
1410 /* A virtual binfo might have been copied from within
1411 another hierarchy. As we're about to use it as a
1412 primary base, make sure the offsets match. */
1420 }
1421 }
1422 }
1424 /* First look for a dynamic direct non-virtual base. */
1426 {
1430 {
1433 }
1434 }
1436 /* A "nearly-empty" virtual base class can be the primary base
1437 class, if no non-virtual polymorphic base can be found. Look for
1438 a nearly-empty virtual dynamic base that is not already a primary
1439 base of something in the hierarchy. If there is no such base,
1440 just pick the first nearly-empty virtual base. */
1446 {
1448 {
1449 /* Found one that is not primary. */
1452 }
1454 /* Remember the first candidate. */
1456 }
1458 found:
1459 /* If we've got a primary base, use it. */
1461 {
1466 /* We are stealing a primary base. */
1470 {
1471 tree delta;
1474 /* A virtual binfo might have been copied from within
1475 another hierarchy. As we're about to use it as a primary
1476 base, make sure the offsets match. */
1481 }
1488 }
1489 }
1491 /* Update the variant types of T. */
1493 void
1495 {
1496 tree variants;
1502 variants;
1504 {
1505 /* These fields are in the _TYPE part of the node, not in
1506 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1516 /* Copy whatever these are holding today. */
1521 /* All variants of a class have the same attributes. */
1523 }
1524 }
1526 \f
1527 /* Set memoizing fields and bits of T (and its variants) for later
1528 use. */
1530 static void
1532 {
1533 /* Fix up variants (if any). */
1537 /* For a class w/o baseclasses, 'finish_struct' has set
1538 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1539 Similarly for a class whose base classes do not have vtables.
1540 When neither of these is true, we might have removed abstract
1541 virtuals (by providing a definition), added some (by declaring
1542 new ones), or redeclared ones from a base class. We need to
1543 recalculate what's really an abstract virtual at this point (by
1544 looking in the vtables). */
1547 /* If this type has a copy constructor or a destructor, force its
1548 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1549 nonzero. This will cause it to be passed by invisible reference
1550 and prevent it from being returned in a register. */
1553 {
1554 tree variants;
1557 {
1560 }
1561 }
1562 }
1564 /* Issue warnings about T having private constructors, but no friends,
1565 and so forth.
1567 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1568 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1569 non-private static member functions. */
1571 static void
1573 {
1576 tree fn;
1579 /* If the class has friends, those entities might create and
1580 access instances, so we should not warn. */
1583 /* We will have warned when the template was declared; there's
1584 no need to warn on every instantiation. */
1586 /* There's no reason to even consider warning about this
1587 class. */
1590 /* We only issue one warning, if more than one applies, because
1591 otherwise, on code like:
1593 class A {
1594 // Oops - forgot `public:'
1595 A();
1596 A(const A&);
1597 ~A();
1598 };
1600 we warn several times about essentially the same problem. */
1602 /* Check to see if all (non-constructor, non-destructor) member
1603 functions are private. (Since there are no friends or
1604 non-private statics, we can't ever call any of the private member
1605 functions.) */
1607 /* We're not interested in compiler-generated methods; they don't
1608 provide any way to call private members. */
1610 {
1612 {
1614 /* A non-private static member function is just like a
1615 friend; it can create and invoke private member
1616 functions, and be accessed without a class
1617 instance. */
1621 /* Keep searching for a static member function. */
1622 }
1625 }
1628 {
1629 /* There are no non-private methods, and there's at least one
1630 private member function that isn't a constructor or
1631 destructor. (If all the private members are
1632 constructors/destructors we want to use the code below that
1633 issues error messages specifically referring to
1634 constructors/destructors.) */
1640 {
1643 }
1645 {
1649 }
1650 }
1652 /* Even if some of the member functions are non-private, the class
1653 won't be useful for much if all the constructors or destructors
1654 are private: such an object can never be created or destroyed. */
1657 {
1660 t);
1662 }
1664 /* Warn about classes that have private constructors and no friends. */
1666 /* Implicitly generated constructors are always public. */
1669 {
1672 /* If a non-template class does not define a copy
1673 constructor, one is defined for it, enabling it to avoid
1674 this warning. For a template class, this does not
1675 happen, and so we would normally get a warning on:
1677 template <class T> class C { private: C(); };
1679 To avoid this asymmetry, we check TYPE_HAS_COPY_CTOR. All
1680 complete non-template or fully instantiated classes have this
1681 flag set. */
1684 else
1686 {
1688 /* Ideally, we wouldn't count copy constructors (or, in
1689 fact, any constructor that takes an argument of the
1690 class type as a parameter) because such things cannot
1691 be used to construct an instance of the class unless
1692 you already have one. But, for now at least, we're
1693 more generous. */
1695 {
1698 }
1699 }
1702 {
1705 t);
1707 }
1708 }
1709 }
1712 gt_pointer_operator new_value;
1716 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1718 static int
1720 {
1733 }
1735 /* This routine compares two fields like method_name_cmp but using the
1736 pointer operator in resort_field_decl_data. */
1738 static int
1740 {
1749 {
1756 }
1758 }
1760 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1762 void
1765 gt_pointer_operator new_value,
1767 {
1771 tree fn;
1773 /* The type conversion ops have to live at the front of the vec, so we
1774 can't sort them. */
1782 {
1786 resort_method_name_cmp);
1787 }
1788 }
1790 /* Warn about duplicate methods in fn_fields.
1792 Sort methods that are not special (i.e., constructors, destructors,
1793 and type conversion operators) so that we can find them faster in
1794 search. */
1796 static void
1798 {
1799 tree fn_fields;
1809 /* Clear DECL_IN_AGGR_P for all functions. */
1814 /* Issue warnings about private constructors and such. If there are
1815 no methods, then some public defaults are generated. */
1818 /* The type conversion ops have to live at the front of the vec, so we
1819 can't sort them. */
1828 }
1830 /* Make BINFO's vtable have N entries, including RTTI entries,
1831 vbase and vcall offsets, etc. Set its type and call the back end
1832 to lay it out. */
1834 static void
1836 {
1837 tree atype;
1838 tree vtable;
1844 /* We may have to grow the vtable. */
1847 {
1851 }
1852 }
1854 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1855 have the same signature. */
1857 int
1859 {
1860 /* One destructor overrides another if they are the same kind of
1861 destructor. */
1865 /* But a non-destructor never overrides a destructor, nor vice
1866 versa, nor do different kinds of destructors override
1867 one-another. For example, a complete object destructor does not
1868 override a deleting destructor. */
1877 {
1885 }
1887 }
1889 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1890 subobject. */
1892 static bool
1894 {
1895 tree probe;
1898 {
1902 /* If we meet a virtual base, we can't follow the inheritance
1903 any more. See if the complete type of DERIVED contains
1904 such a virtual base. */
1907 }
1909 }
1912 /* The function for which we are trying to find a final overrider. */
1913 tree fn;
1914 /* The base class in which the function was declared. */
1915 tree declaring_base;
1916 /* The candidate overriders. */
1917 tree candidates;
1918 /* Path to most derived. */
1922 /* Add the overrider along the current path to FFOD->CANDIDATES.
1923 Returns true if an overrider was found; false otherwise. */
1925 static bool
1929 {
1930 tree method;
1932 /* If BINFO is not the most derived type, try a more derived class.
1933 A definition there will overrider a definition here. */
1935 {
1936 depth--;
1940 }
1944 {
1947 /* Remove any candidates overridden by this new function. */
1949 {
1950 /* If *CANDIDATE overrides METHOD, then METHOD
1951 cannot override anything else on the list. */
1954 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1957 else
1959 }
1961 /* Add the new function. */
1964 }
1967 }
1969 /* Called from find_final_overrider via dfs_walk. */
1971 static tree
1973 {
1981 }
1983 static tree
1985 {
1990 }
1992 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1993 FN and whose TREE_VALUE is the binfo for the base where the
1994 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1995 DERIVED) is the base object in which FN is declared. */
1997 static tree
1999 {
2000 find_final_overrider_data ffod;
2002 /* Getting this right is a little tricky. This is valid:
2004 struct S { virtual void f (); };
2005 struct T { virtual void f (); };
2006 struct U : public S, public T { };
2008 even though calling `f' in `U' is ambiguous. But,
2010 struct R { virtual void f(); };
2011 struct S : virtual public R { virtual void f (); };
2012 struct T : virtual public R { virtual void f (); };
2013 struct U : public S, public T { };
2015 is not -- there's no way to decide whether to put `S::f' or
2016 `T::f' in the vtable for `R'.
2018 The solution is to look at all paths to BINFO. If we find
2019 different overriders along any two, then there is a problem. */
2023 /* Determine the depth of the hierarchy. */
2034 /* If there was no winner, issue an error message. */
2039 }
2041 /* Return the index of the vcall offset for FN when TYPE is used as a
2042 virtual base. */
2044 static tree
2046 {
2048 tree_pair_p p;
2056 /* There should always be an appropriate index. */
2058 }
2060 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2061 dominated by T. FN is the old function; VIRTUALS points to the
2062 corresponding position in the new BINFO_VIRTUALS list. IX is the index
2063 of that entry in the list. */
2065 static void
2068 {
2069 tree b;
2070 tree overrider;
2071 tree delta;
2072 tree virtual_base;
2073 tree first_defn;
2079 /* Find the nearest primary base (possibly binfo itself) which defines
2080 this function; this is the class the caller will convert to when
2081 calling FN through BINFO. */
2083 {
2088 /* The nearest definition is from a lost primary. */
2091 }
2094 /* Find the final overrider. */
2097 {
2100 }
2103 /* Check for adjusting covariant return types. */
2111 /* If the overrider is invalid, don't even try. */
2113 {
2114 /* If FN is a covariant thunk, we must figure out the adjustment
2115 to the final base FN was converting to. As OVERRIDER_TARGET might
2116 also be converting to the return type of FN, we have to
2117 combine the two conversions here. */
2124 {
2128 }
2129 else
2133 /* Find the equivalent binfo within the return type of the
2134 overriding function. We will want the vbase offset from
2135 there. */
2137 over_return);
2140 {
2141 /* There was no existing virtual thunk (which takes
2142 precedence). So find the binfo of the base function's
2143 return type within the overriding function's return type.
2144 We cannot call lookup base here, because we're inside a
2145 dfs_walk, and will therefore clobber the BINFO_MARKED
2146 flags. Fortunately we know the covariancy is valid (it
2147 has already been checked), so we can just iterate along
2148 the binfos, which have been chained in inheritance graph
2149 order. Of course it is lame that we have to repeat the
2150 search here anyway -- we should really be caching pieces
2151 of the vtable and avoiding this repeated work. */
2154 /* Find the base binfo within the overriding function's
2155 return type. We will always find a thunk_binfo, except
2156 when the covariancy is invalid (which we will have
2157 already diagnosed). */
2160 thunk_binfo;
2166 /* See if virtual inheritance is involved. */
2168 virtual_offset;
2175 {
2179 {
2180 /* We convert via virtual base. Adjust the fixed
2181 offset to be from there. */
2182 offset =
2186 }
2188 /* There was an existing fixed offset, this must be
2189 from the base just converted to, and the base the
2190 FN was thunking to. */
2192 else
2194 }
2195 }
2198 /* Replace the overriding function with a covariant thunk. We
2199 will emit the overriding function in its own slot as
2200 well. */
2203 }
2204 else
2208 /* If we need a covariant thunk, then we may need to adjust first_defn.
2209 The ABI specifies that the thunks emitted with a function are
2210 determined by which bases the function overrides, so we need to be
2211 sure that we're using a thunk for some overridden base; even if we
2212 know that the necessary this adjustment is zero, there may not be an
2213 appropriate zero-this-adjusment thunk for us to use since thunks for
2214 overriding virtual bases always use the vcall offset.
2216 Furthermore, just choosing any base that overrides this function isn't
2217 quite right, as this slot won't be used for calls through a type that
2218 puts a covariant thunk here. Calling the function through such a type
2219 will use a different slot, and that slot is the one that determines
2220 the thunk emitted for that base.
2222 So, keep looking until we find the base that we're really overriding
2223 in this slot: the nearest primary base that doesn't use a covariant
2224 thunk in this slot. */
2226 {
2228 /* We already know that the overrider needs a covariant thunk. */
2231 {
2238 }
2240 }
2242 /* Assume that we will produce a thunk that convert all the way to
2243 the final overrider, and not to an intermediate virtual base. */
2246 /* See if we can convert to an intermediate virtual base first, and then
2247 use the vcall offset located there to finish the conversion. */
2249 {
2250 /* If we find the final overrider, then we can stop
2251 walking. */
2256 /* If we find a virtual base, and we haven't yet found the
2257 overrider, then there is a virtual base between the
2258 declaring base (first_defn) and the final overrider. */
2260 {
2263 }
2264 }
2266 /* Compute the constant adjustment to the `this' pointer. The
2267 `this' pointer, when this function is called, will point at BINFO
2268 (or one of its primary bases, which are at the same offset). */
2270 /* The `this' pointer needs to be adjusted from the declaration to
2271 the nearest virtual base. */
2276 /* If the nearest definition is in a lost primary, we don't need an
2277 entry in our vtable. Except possibly in a constructor vtable,
2278 if we happen to get our primary back. In that case, the offset
2279 will be zero, as it will be a primary base. */
2281 else
2282 /* The `this' pointer needs to be adjusted from pointing to
2283 BINFO to pointing at the base where the final overrider
2284 appears. */
2295 else
2300 }
2302 /* Called from modify_all_vtables via dfs_walk. */
2304 static tree
2306 {
2308 tree virtuals;
2309 tree old_virtuals;
2313 /* A base without a vtable needs no modification, and its bases
2314 are uninteresting. */
2319 /* Don't do the primary vtable, if it's new. */
2323 /* There's no need to modify the vtable for a non-virtual primary
2324 base; we're not going to use that vtable anyhow. We do still
2325 need to do this for virtual primary bases, as they could become
2326 non-primary in a construction vtable. */
2331 /* Now, go through each of the virtual functions in the virtual
2332 function table for BINFO. Find the final overrider, and update
2333 the BINFO_VIRTUALS list appropriately. */
2336 virtuals;
2340 binfo,
2345 }
2347 /* Update all of the primary and secondary vtables for T. Create new
2348 vtables as required, and initialize their RTTI information. Each
2349 of the functions in VIRTUALS is declared in T and may override a
2350 virtual function from a base class; find and modify the appropriate
2351 entries to point to the overriding functions. Returns a list, in
2352 declaration order, of the virtual functions that are declared in T,
2353 but do not appear in the primary base class vtable, and which
2354 should therefore be appended to the end of the vtable for T. */
2356 static tree
2358 {
2362 /* Update all of the vtables. */
2365 /* Add virtual functions not already in our primary vtable. These
2366 will be both those introduced by this class, and those overridden
2367 from secondary bases. It does not include virtuals merely
2368 inherited from secondary bases. */
2370 {
2375 {
2376 /* We don't need to adjust the `this' pointer when
2377 calling this function. */
2381 /* This is a function not already in our vtable. Keep it. */
2383 }
2384 else
2385 /* We've already got an entry for this function. Skip it. */
2387 }
2390 }
2392 /* Get the base virtual function declarations in T that have the
2393 indicated NAME. */
2395 static tree
2397 {
2398 tree methods;
2403 /* Find virtual functions in T with the indicated NAME. */
2407 methods;
2409 {
2415 }
2421 {
2424 base_fndecls);
2425 }
2428 }
2430 /* If this declaration supersedes the declaration of
2431 a method declared virtual in the base class, then
2432 mark this field as being virtual as well. */
2434 void
2436 {
2438 /* In [temp.mem] we have:
2440 A specialization of a member function template does not
2441 override a virtual function from a base class. */
2448 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2449 the error_mark_node so that we know it is an overriding
2450 function. */
2454 {
2458 }
2459 }
2461 /* Warn about hidden virtual functions that are not overridden in t.
2462 We know that constructors and destructors don't apply. */
2464 static void
2466 {
2468 tree fns;
2471 /* We go through each separately named virtual function. */
2475 {
2476 tree fn;
2477 tree name;
2478 tree fndecl;
2479 tree base_fndecls;
2480 tree base_binfo;
2481 tree binfo;
2484 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2485 have the same name. Figure out what name that is. */
2487 /* There are no possibly hidden functions yet. */
2489 /* Iterate through all of the base classes looking for possibly
2490 hidden functions. */
2493 {
2496 base_fndecls);
2497 }
2499 /* If there are no functions to hide, continue. */
2503 /* Remove any overridden functions. */
2505 {
2508 {
2512 /* If the method from the base class has the same
2513 signature as the method from the derived class, it
2514 has been overridden. */
2517 else
2519 }
2520 }
2522 /* Now give a warning for all base functions without overriders,
2523 as they are hidden. */
2525 {
2526 /* Here we know it is a hider, and no overrider exists. */
2530 }
2531 }
2532 }
2534 /* Check for things that are invalid. There are probably plenty of other
2535 things we should check for also. */
2537 static void
2539 {
2540 tree field;
2543 {
2551 {
2555 {
2556 /* We're generally only interested in entities the user
2557 declared, but we also find nested classes by noticing
2558 the TYPE_DECL that we create implicitly. You're
2559 allowed to put one anonymous union inside another,
2560 though, so we explicitly tolerate that. We use
2561 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2562 we also allow unnamed types used for defining fields. */
2569 {
2573 else
2577 }
2580 {
2583 else
2585 }
2587 {
2590 else
2592 }
2596 }
2597 }
2598 }
2599 }
2601 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2602 will be used later during class template instantiation.
2603 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2604 a non-static member data (FIELD_DECL), a member function
2605 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2606 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2607 When FRIEND_P is nonzero, T is either a friend class
2608 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2609 (FUNCTION_DECL, TEMPLATE_DECL). */
2611 void
2613 {
2614 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2619 }
2621 /* Create default constructors, assignment operators, and so forth for
2622 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2623 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2624 the class cannot have a default constructor, copy constructor
2625 taking a const reference argument, or an assignment operator taking
2626 a const reference, respectively. */
2628 static void
2632 {
2633 /* Destructor. */
2635 {
2636 /* In general, we create destructors lazily. */
2641 /* But if this is a Java class, any non-trivial destructor is
2642 invalid, even if compiler-generated. Therefore, if the
2643 destructor is non-trivial we create it now. */
2645 }
2647 /* [class.ctor]
2649 If there is no user-declared constructor for a class, a default
2650 constructor is implicitly declared. */
2652 {
2655 }
2657 /* [class.ctor]
2659 If a class definition does not explicitly declare a copy
2660 constructor, one is declared implicitly. */
2663 {
2669 }
2671 /* If there is no assignment operator, one will be created if and
2672 when it is needed. For now, just record whether or not the type
2673 of the parameter to the assignment operator will be a const or
2674 non-const reference. */
2677 {
2683 }
2685 /* We can't be lazy about declaring functions that might override
2686 a virtual function from a base class. */
2691 {
2693 tree base_binfo;
2697 {
2698 tree bv;
2700 {
2703 {
2708 }
2712 }
2713 }
2714 }
2715 }
2717 /* Subroutine of finish_struct_1. Recursively count the number of fields
2718 in TYPE, including anonymous union members. */
2720 static int
2722 {
2723 tree x;
2726 {
2729 else
2731 }
2733 }
2735 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2736 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2738 static int
2740 {
2741 tree x;
2743 {
2746 else
2748 }
2750 }
2752 /* FIELD is a bit-field. We are finishing the processing for its
2753 enclosing type. Issue any appropriate messages and set appropriate
2754 flags. Returns false if an error has been diagnosed. */
2756 static bool
2758 {
2760 tree w;
2762 /* Extract the declared width of the bitfield, which has been
2763 temporarily stashed in DECL_INITIAL. */
2766 /* Remove the bit-field width indicator so that the rest of the
2767 compiler does not treat that value as an initializer. */
2770 /* Detect invalid bit-field type. */
2772 {
2775 }
2776 else
2777 {
2778 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2781 /* detect invalid field size. */
2785 {
2788 }
2790 {
2793 }
2795 {
2798 }
2807 }
2810 {
2814 }
2815 else
2816 {
2817 /* Non-bit-fields are aligned for their type. */
2821 }
2822 }
2824 /* FIELD is a non bit-field. We are finishing the processing for its
2825 enclosing type T. Issue any appropriate messages and set appropriate
2826 flags. */
2828 static void
2830 tree t,
2834 {
2837 /* In C++98 an anonymous union cannot contain any fields which would change
2838 the settings of CANT_HAVE_CONST_CTOR and friends. */
2840 ;
2841 /* And, we don't set TYPE_HAS_CONST_COPY_CTOR, etc., for anonymous
2842 structs. So, we recurse through their fields here. */
2844 {
2845 tree fields;
2851 }
2852 /* Check members with class type for constructors, destructors,
2853 etc. */
2855 {
2856 /* Never let anything with uninheritable virtuals
2857 make it through without complaint. */
2861 {
2866 field);
2871 field);
2873 {
2877 }
2878 }
2879 else
2880 {
2893 }
2902 }
2904 {
2905 /* `build_class_init_list' does not recognize
2906 non-FIELD_DECLs. */
2910 }
2911 }
2913 /* Check the data members (both static and non-static), class-scoped
2914 typedefs, etc., appearing in the declaration of T. Issue
2915 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2916 declaration order) of access declarations; each TREE_VALUE in this
2917 list is a USING_DECL.
2919 In addition, set the following flags:
2921 EMPTY_P
2922 The class is empty, i.e., contains no non-static data members.
2924 CANT_HAVE_CONST_CTOR_P
2925 This class cannot have an implicitly generated copy constructor
2926 taking a const reference.
2928 CANT_HAVE_CONST_ASN_REF
2929 This class cannot have an implicitly generated assignment
2930 operator taking a const reference.
2932 All of these flags should be initialized before calling this
2933 function.
2935 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2936 fields can be added by adding to this chain. */
2938 static void
2942 {
2950 /* Assume there are no access declarations. */
2952 /* Assume this class has no pointer members. */
2954 /* Assume none of the members of this class have default
2955 initializations. */
2959 {
2967 {
2968 /* Prune the access declaration from the list of fields. */
2971 /* Save the access declarations for our caller. */
2974 /* Since we've reset *FIELD there's no reason to skip to the
2975 next field. */
2978 }
2984 /* If we've gotten this far, it's a data member, possibly static,
2985 or an enumerator. */
2988 /* When this goes into scope, it will be a non-local reference. */
2992 {
2993 /* [class.union]
2995 If a union contains a static data member, or a member of
2996 reference type, the program is ill-formed. */
2998 {
3001 }
3003 {
3008 }
3009 }
3011 /* Perform error checking that did not get done in
3012 grokdeclarator. */
3014 {
3018 }
3020 {
3024 }
3032 /* Now it can only be a FIELD_DECL. */
3037 /* A standard-layout class is a class that:
3038 ...
3039 has the same access control (Clause 11) for all non-static data members,
3040 ... */
3047 /* If this is of reference type, check if it needs an init. */
3049 {
3055 /* ARM $12.6.2: [A member initializer list] (or, for an
3056 aggregate, initialization by a brace-enclosed list) is the
3057 only way to initialize nonstatic const and reference
3058 members. */
3061 }
3066 {
3068 {
3069 warning
3072 x);
3074 }
3078 }
3081 /* We don't treat zero-width bitfields as making a class
3082 non-empty. */
3083 ;
3084 else
3085 {
3086 /* The class is non-empty. */
3088 /* The class is not even nearly empty. */
3090 /* If one of the data members contains an empty class,
3091 so does T. */
3095 }
3097 /* This is used by -Weffc++ (see below). Warn only for pointers
3098 to members which might hold dynamic memory. So do not warn
3099 for pointers to functions or pointers to members. */
3106 {
3111 }
3117 /* DR 148 now allows pointers to members (which are POD themselves),
3118 to be allowed in POD structs. */
3127 /* We set DECL_C_BIT_FIELD in grokbitfield.
3128 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3131 cant_have_const_ctor_p,
3132 no_const_asn_ref_p,
3135 /* If any field is const, the structure type is pseudo-const. */
3137 {
3142 /* ARM $12.6.2: [A member initializer list] (or, for an
3143 aggregate, initialization by a brace-enclosed list) is the
3144 only way to initialize nonstatic const and reference
3145 members. */
3148 }
3149 /* A field that is pseudo-const makes the structure likewise. */
3151 {
3156 }
3158 /* Core issue 80: A nonstatic data member is required to have a
3159 different name from the class iff the class has a
3160 user-declared constructor. */
3164 }
3166 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3167 it should also define a copy constructor and an assignment operator to
3168 implement the correct copy semantic (deep vs shallow, etc.). As it is
3169 not feasible to check whether the constructors do allocate dynamic memory
3170 and store it within members, we approximate the warning like this:
3172 -- Warn only if there are members which are pointers
3173 -- Warn only if there is a non-trivial constructor (otherwise,
3174 there cannot be memory allocated).
3175 -- Warn only if there is a non-trivial destructor. We assume that the
3176 user at least implemented the cleanup correctly, and a destructor
3177 is needed to free dynamic memory.
3179 This seems enough for practical purposes. */
3181 && has_pointers
3185 {
3189 {
3194 }
3198 }
3200 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3204 /* Check anonymous struct/anonymous union fields. */
3207 /* We've built up the list of access declarations in reverse order.
3208 Fix that now. */
3210 }
3212 /* If TYPE is an empty class type, records its OFFSET in the table of
3213 OFFSETS. */
3215 static int
3217 {
3218 splay_tree_node n;
3223 /* Record the location of this empty object in OFFSETS. */
3231 type,
3235 }
3237 /* Returns nonzero if TYPE is an empty class type and there is
3238 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3240 static int
3242 {
3243 splay_tree_node n;
3244 tree t;
3249 /* Record the location of this empty object in OFFSETS. */
3259 }
3261 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3262 F for every subobject, passing it the type, offset, and table of
3263 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3264 be traversed.
3266 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3267 than MAX_OFFSET will not be walked.
3269 If F returns a nonzero value, the traversal ceases, and that value
3270 is returned. Otherwise, returns zero. */
3272 static int
3274 subobject_offset_fn f,
3275 tree offset,
3276 splay_tree offsets,
3277 tree max_offset,
3279 {
3283 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3284 stop. */
3292 {
3296 }
3299 {
3300 tree field;
3301 tree binfo;
3304 /* Avoid recursing into objects that are not interesting. */
3308 /* Record the location of TYPE. */
3313 /* Iterate through the direct base classes of TYPE. */
3317 {
3318 tree binfo_offset;
3331 offset,
3333 else
3334 {
3335 tree orig_binfo;
3336 /* We cannot rely on BINFO_OFFSET being set for the base
3337 class yet, but the offsets for direct non-virtual
3338 bases can be calculated by going back to the TYPE. */
3341 offset,
3343 }
3346 f,
3347 binfo_offset,
3348 offsets,
3349 max_offset,
3354 }
3357 {
3361 /* Iterate through the virtual base classes of TYPE. In G++
3362 3.2, we included virtual bases in the direct base class
3363 loop above, which results in incorrect results; the
3364 correct offsets for virtual bases are only known when
3365 working with the most derived type. */
3369 {
3371 f,
3373 offset,
3375 offsets,
3376 max_offset,
3380 }
3381 else
3382 {
3383 /* We still have to walk the primary base, if it is
3384 virtual. (If it is non-virtual, then it was walked
3385 above.) */
3391 {
3392 r = (walk_subobject_offsets
3397 }
3398 }
3399 }
3401 /* Iterate through the fields of TYPE. */
3404 {
3405 tree field_offset;
3409 else
3410 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3414 f,
3416 offset,
3417 field_offset),
3418 offsets,
3419 max_offset,
3423 }
3424 }
3426 {
3429 tree index;
3431 /* Avoid recursing into objects that are not interesting. */
3436 /* Step through each of the elements in the array. */
3438 /* G++ 3.2 had an off-by-one error here. */
3443 {
3445 f,
3446 offset,
3447 offsets,
3448 max_offset,
3454 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3455 there's no point in iterating through the remaining
3456 elements of the array. */
3459 }
3460 }
3463 }
3465 /* Record all of the empty subobjects of TYPE (either a type or a
3466 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3467 is being placed at OFFSET; otherwise, it is a base class that is
3468 being placed at OFFSET. */
3470 static void
3472 tree offset,
3473 splay_tree offsets,
3475 {
3476 tree max_offset;
3477 /* If recording subobjects for a non-static data member or a
3478 non-empty base class , we do not need to record offsets beyond
3479 the size of the biggest empty class. Additional data members
3480 will go at the end of the class. Additional base classes will go
3481 either at offset zero (if empty, in which case they cannot
3482 overlap with offsets past the size of the biggest empty class) or
3483 at the end of the class.
3485 However, if we are placing an empty base class, then we must record
3486 all offsets, as either the empty class is at offset zero (where
3487 other empty classes might later be placed) or at the end of the
3488 class (where other objects might then be placed, so other empty
3489 subobjects might later overlap). */
3493 else
3497 }
3499 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3500 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3501 virtual bases of TYPE are examined. */
3503 static int
3505 tree offset,
3506 splay_tree offsets,
3508 {
3509 splay_tree_node max_node;
3511 /* Get the node in OFFSETS that indicates the maximum offset where
3512 an empty subobject is located. */
3514 /* If there aren't any empty subobjects, then there's no point in
3515 performing this check. */
3521 vbases_p);
3522 }
3524 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3525 non-static data member of the type indicated by RLI. BINFO is the
3526 binfo corresponding to the base subobject, OFFSETS maps offsets to
3527 types already located at those offsets. This function determines
3528 the position of the DECL. */
3530 static void
3532 tree decl,
3533 tree binfo,
3534 splay_tree offsets)
3535 {
3538 tree type;
3541 {
3542 /* For the purposes of determining layout conflicts, we want to
3543 use the class type of BINFO; TREE_TYPE (DECL) will be the
3544 CLASSTYPE_AS_BASE version, which does not contain entries for
3545 zero-sized bases. */
3548 }
3549 else
3550 {
3553 }
3555 /* Try to place the field. It may take more than one try if we have
3556 a hard time placing the field without putting two objects of the
3557 same type at the same address. */
3559 {
3562 /* Place this field. */
3566 /* We have to check to see whether or not there is already
3567 something of the same type at the offset we're about to use.
3568 For example, consider:
3570 struct S {};
3571 struct T : public S { int i; };
3572 struct U : public S, public T {};
3574 Here, we put S at offset zero in U. Then, we can't put T at
3575 offset zero -- its S component would be at the same address
3576 as the S we already allocated. So, we have to skip ahead.
3577 Since all data members, including those whose type is an
3578 empty class, have nonzero size, any overlap can happen only
3579 with a direct or indirect base-class -- it can't happen with
3580 a data member. */
3581 /* In a union, overlap is permitted; all members are placed at
3582 offset zero. */
3585 /* G++ 3.2 did not check for overlaps when placing a non-empty
3586 virtual base. */
3591 {
3592 /* Strip off the size allocated to this field. That puts us
3593 at the first place we could have put the field with
3594 proper alignment. */
3597 /* Bump up by the alignment required for the type. */
3598 rli->bitpos
3604 }
3605 else
3606 /* There was no conflict. We're done laying out this field. */
3608 }
3610 /* Now that we know where it will be placed, update its
3611 BINFO_OFFSET. */
3613 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3614 this point because their BINFO_OFFSET is copied from another
3615 hierarchy. Therefore, we may not need to add the entire
3616 OFFSET. */
3622 }
3624 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3626 static int
3628 tree offset,
3629 splay_tree offsets ATTRIBUTE_UNUSED)
3630 {
3632 }
3634 /* Layout the empty base BINFO. EOC indicates the byte currently just
3635 past the end of the class, and should be correctly aligned for a
3636 class of the type indicated by BINFO; OFFSETS gives the offsets of
3637 the empty bases allocated so far. T is the most derived
3638 type. Return nonzero iff we added it at the end. */
3640 static bool
3643 {
3644 tree alignment;
3648 /* This routine should only be used for empty classes. */
3653 {
3655 propagate_binfo_offsets
3658 else
3660 "offset of empty base %qT may not be ABI-compliant and may"
3663 }
3665 /* This is an empty base class. We first try to put it at offset
3666 zero. */
3669 offsets,
3671 {
3672 /* That didn't work. Now, we move forward from the next
3673 available spot in the class. */
3677 {
3680 offsets,
3682 /* We finally found a spot where there's no overlap. */
3685 /* There's overlap here, too. Bump along to the next spot. */
3687 }
3688 }
3691 {
3696 }
3699 }
3701 /* Layout the base given by BINFO in the class indicated by RLI.
3702 *BASE_ALIGN is a running maximum of the alignments of
3703 any base class. OFFSETS gives the location of empty base
3704 subobjects. T is the most derived type. Return nonzero if the new
3705 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3706 *NEXT_FIELD, unless BINFO is for an empty base class.
3708 Returns the location at which the next field should be inserted. */
3713 {
3718 /* This error is now reported in xref_tag, thus giving better
3719 location information. */
3722 /* Place the base class. */
3724 {
3725 tree decl;
3727 /* The containing class is non-empty because it has a non-empty
3728 base class. */
3731 /* Create the FIELD_DECL. */
3738 {
3746 /* Try to place the field. It may take more than one try if we
3747 have a hard time placing the field without putting two
3748 objects of the same type at the same address. */
3750 /* Add the new FIELD_DECL to the list of fields for T. */
3754 }
3755 }
3756 else
3757 {
3758 tree eoc;
3761 /* On some platforms (ARM), even empty classes will not be
3762 byte-aligned. */
3767 /* A nearly-empty class "has no proper base class that is empty,
3768 not morally virtual, and at an offset other than zero." */
3770 {
3773 /* The check above (used in G++ 3.2) is insufficient because
3774 an empty class placed at offset zero might itself have an
3775 empty base at a nonzero offset. */
3777 empty_base_at_nonzero_offset_p,
3778 size_zero_node,
3782 {
3785 else
3787 "class %qT will be considered nearly empty in a "
3789 }
3790 }
3792 /* We do not create a FIELD_DECL for empty base classes because
3793 it might overlap some other field. We want to be able to
3794 create CONSTRUCTORs for the class by iterating over the
3795 FIELD_DECLs, and the back end does not handle overlapping
3796 FIELD_DECLs. */
3798 /* An empty virtual base causes a class to be non-empty
3799 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3800 here because that was already done when the virtual table
3801 pointer was created. */
3802 }
3804 /* Record the offsets of BINFO and its base subobjects. */
3807 offsets,
3811 }
3813 /* Layout all of the non-virtual base classes. Record empty
3814 subobjects in OFFSETS. T is the most derived type. Return nonzero
3815 if the type cannot be nearly empty. The fields created
3816 corresponding to the base classes will be inserted at
3817 *NEXT_FIELD. */
3819 static void
3822 {
3823 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3824 subobjects. */
3829 /* The primary base class is always allocated first. */
3834 /* Now allocate the rest of the bases. */
3836 {
3837 tree base_binfo;
3841 /* The primary base was already allocated above, so we don't
3842 need to allocate it again here. */
3846 /* Virtual bases are added at the end (a primary virtual base
3847 will have already been added). */
3853 }
3854 }
3856 /* Go through the TYPE_METHODS of T issuing any appropriate
3857 diagnostics, figuring out which methods override which other
3858 methods, and so forth. */
3860 static void
3862 {
3863 tree x;
3866 {
3870 /* The name of the field is the original field name
3871 Save this in auxiliary field for later overloading. */
3873 {
3877 }
3878 /* All user-provided destructors are non-trivial.
3879 Constructors and assignment ops are handled in
3880 grok_special_member_properties. */
3883 }
3884 }
3886 /* FN is a constructor or destructor. Clone the declaration to create
3887 a specialized in-charge or not-in-charge version, as indicated by
3888 NAME. */
3890 static tree
3892 {
3893 tree parms;
3894 tree clone;
3896 /* Copy the function. */
3898 /* Reset the function name. */
3901 /* Remember where this function came from. */
3903 /* Make it easy to find the CLONE given the FN. */
3907 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
3909 {
3916 }
3919 /* There's no pending inline data for this function. */
3923 /* The base-class destructor is not virtual. */
3925 {
3929 }
3931 /* If there was an in-charge parameter, drop it from the function
3932 type. */
3934 {
3935 tree basetype;
3936 tree parmtypes;
3937 tree exceptions;
3942 /* Skip the `this' parameter. */
3944 /* Skip the in-charge parameter. */
3946 /* And the VTT parm, in a complete [cd]tor. */
3950 /* If this is subobject constructor or destructor, add the vtt
3951 parameter. */
3955 parmtypes);
3958 exceptions);
3962 }
3964 /* Copy the function parameters. */
3966 /* Remove the in-charge parameter. */
3968 {
3972 }
3973 /* And the VTT parm, in a complete [cd]tor. */
3975 {
3978 else
3979 {
3983 }
3984 }
3987 {
3990 }
3992 /* Create the RTL for this function. */
4000 }
4002 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
4003 not invoke this function directly.
4005 For a non-thunk function, returns the address of the slot for storing
4006 the function it is a clone of. Otherwise returns NULL_TREE.
4008 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
4009 cloned_function is unset. This is to support the separate
4010 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
4011 on a template makes sense, but not the former. */
4013 tree *
4015 {
4023 {
4024 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
4027 else
4028 #endif
4030 }
4035 else
4037 }
4039 /* Produce declarations for all appropriate clones of FN. If
4040 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4041 CLASTYPE_METHOD_VEC as well. */
4043 void
4045 {
4046 tree clone;
4048 /* Avoid inappropriate cloning. */
4054 {
4055 /* For each constructor, we need two variants: an in-charge version
4056 and a not-in-charge version. */
4063 }
4064 else
4065 {
4068 /* For each destructor, we need three variants: an in-charge
4069 version, a not-in-charge version, and an in-charge deleting
4070 version. We clone the deleting version first because that
4071 means it will go second on the TYPE_METHODS list -- and that
4072 corresponds to the correct layout order in the virtual
4073 function table.
4075 For a non-virtual destructor, we do not build a deleting
4076 destructor. */
4078 {
4082 }
4089 }
4091 /* Note that this is an abstract function that is never emitted. */
4093 }
4095 /* DECL is an in charge constructor, which is being defined. This will
4096 have had an in class declaration, from whence clones were
4097 declared. An out-of-class definition can specify additional default
4098 arguments. As it is the clones that are involved in overload
4099 resolution, we must propagate the information from the DECL to its
4100 clones. */
4102 void
4104 {
4105 tree clone;
4109 {
4116 /* Skip the 'this' parameter. */
4132 {
4137 {
4138 /* A default parameter has been added. Adjust the
4139 clone's parameters. */
4143 tree type;
4148 {
4151 clone_parms);
4153 }
4156 clone_parms);
4165 }
4166 }
4168 }
4169 }
4171 /* For each of the constructors and destructors in T, create an
4172 in-charge and not-in-charge variant. */
4174 static void
4176 {
4177 tree fns;
4179 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4180 out now. */
4188 }
4190 /* Returns true iff class T has a user-defined constructor other than
4191 the default constructor. */
4193 bool
4195 {
4196 tree fns;
4202 {
4209 }
4212 }
4214 /* Returns the defaulted constructor if T has one. Otherwise, returns
4215 NULL_TREE. */
4217 tree
4219 {
4226 {
4230 {
4236 }
4237 }
4240 }
4242 /* Returns true iff FN is a user-provided function, i.e. user-declared
4243 and not defaulted at its first declaration; or explicit, private,
4244 protected, or non-const. */
4246 bool
4248 {
4251 else
4254 }
4256 /* Returns true iff class T has a user-provided constructor. */
4258 bool
4260 {
4261 tree fns;
4269 /* This can happen in error cases; avoid crashing. */
4278 }
4280 /* Returns true iff class T has a user-provided default constructor. */
4282 bool
4284 {
4285 tree fns;
4291 {
4297 }
4300 }
4302 /* Returns true iff class TYPE has a virtual destructor. */
4304 bool
4306 {
4307 tree dtor;
4315 }
4317 /* Returns true iff class T has a move constructor. */
4319 bool
4321 {
4322 tree fns;
4325 {
4328 }
4338 }
4340 /* Returns true iff class T has a move assignment operator. */
4342 bool
4344 {
4345 tree fns;
4348 {
4351 }
4359 }
4361 /* Remove all zero-width bit-fields from T. */
4363 static void
4365 {
4370 {
4373 /* We should not be confused by the fact that grokbitfield
4374 temporarily sets the width of the bit field into
4375 DECL_INITIAL (*fieldsp).
4376 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
4377 to that width. */
4380 else
4382 }
4383 }
4385 /* Returns TRUE iff we need a cookie when dynamically allocating an
4386 array whose elements have the indicated class TYPE. */
4388 static bool
4390 {
4391 tree fns;
4396 /* If there's a non-trivial destructor, we need a cookie. In order
4397 to iterate through the array calling the destructor for each
4398 element, we'll have to know how many elements there are. */
4402 /* If the usual deallocation function is a two-argument whose second
4403 argument is of type `size_t', then we have to pass the size of
4404 the array to the deallocation function, so we will need to store
4405 a cookie. */
4409 /* If there are no `operator []' members, or the lookup is
4410 ambiguous, then we don't need a cookie. */
4413 /* Loop through all of the functions. */
4415 {
4416 tree fn;
4417 tree second_parm;
4419 /* Select the current function. */
4421 /* See if this function is a one-argument delete function. If
4422 it is, then it will be the usual deallocation function. */
4426 /* Do not consider this function if its second argument is an
4427 ellipsis. */
4430 /* Otherwise, if we have a two-argument function and the second
4431 argument is `size_t', it will be the usual deallocation
4432 function -- unless there is one-argument function, too. */
4436 }
4439 }
4441 /* Check the validity of the bases and members declared in T. Add any
4442 implicitly-generated functions (like copy-constructors and
4443 assignment operators). Compute various flag bits (like
4444 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
4445 level: i.e., independently of the ABI in use. */
4447 static void
4449 {
4450 /* Nonzero if the implicitly generated copy constructor should take
4451 a non-const reference argument. */
4453 /* Nonzero if the implicitly generated assignment operator
4454 should take a non-const reference argument. */
4456 tree access_decls;
4459 tree fn;
4461 /* By default, we use const reference arguments and generate default
4462 constructors. */
4466 /* Check all the base-classes. */
4470 /* Check all the method declarations. */
4473 /* Save the initial values of these flags which only indicate whether
4474 or not the class has user-provided functions. As we analyze the
4475 bases and members we can set these flags for other reasons. */
4479 /* Check all the data member declarations. We cannot call
4480 check_field_decls until we have called check_bases check_methods,
4481 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4482 being set appropriately. */
4487 /* A nearly-empty class has to be vptr-containing; a nearly empty
4488 class contains just a vptr. */
4492 /* Do some bookkeeping that will guide the generation of implicitly
4493 declared member functions. */
4496 /* We need to call a constructor for this class if it has a
4497 user-provided constructor, or if the default constructor is going
4498 to initialize the vptr. (This is not an if-and-only-if;
4499 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4500 themselves need constructing.) */
4503 /* [dcl.init.aggr]
4505 An aggregate is an array or a class with no user-provided
4506 constructors ... and no virtual functions.
4508 Again, other conditions for being an aggregate are checked
4509 elsewhere. */
4512 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
4513 retain the old definition internally for ABI reasons. */
4522 /* If the class has no user-declared constructor, but does have
4523 non-static const or reference data members that can never be
4524 initialized, issue a warning. */
4526 /* Classes with user-declared constructors are presumed to
4527 initialize these members. */
4529 /* Aggregates can be initialized with brace-enclosed
4530 initializers. */
4532 {
4533 tree field;
4536 {
4537 tree type;
4551 }
4552 }
4554 /* Synthesize any needed methods. */
4556 cant_have_const_ctor,
4557 no_const_asn_ref);
4559 /* Check defaulted declarations here so we have cant_have_const_ctor
4560 and don't need to worry about clones. */
4563 {
4566 {
4567 bool imp_const_p
4573 /* If the function is defaulted outside the class, we just
4574 give the synthesis error. */
4580 }
4582 }
4585 {
4586 /* "The closure type associated with a lambda-expression has a deleted
4587 default constructor and a deleted copy assignment operator." */
4593 /* "This class type is not an aggregate." */
4595 }
4597 /* Create the in-charge and not-in-charge variants of constructors
4598 and destructors. */
4601 /* Process the using-declarations. */
4605 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4608 /* Figure out whether or not we will need a cookie when dynamically
4609 allocating an array of this type. */
4612 }
4614 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4615 accordingly. If a new vfield was created (because T doesn't have a
4616 primary base class), then the newly created field is returned. It
4617 is not added to the TYPE_FIELDS list; it is the caller's
4618 responsibility to do that. Accumulate declared virtual functions
4619 on VIRTUALS_P. */
4621 static tree
4623 {
4624 tree fn;
4626 /* Collect the virtual functions declared in T. */
4630 {
4639 }
4641 /* If we couldn't find an appropriate base class, create a new field
4642 here. Even if there weren't any new virtual functions, we might need a
4643 new virtual function table if we're supposed to include vptrs in
4644 all classes that need them. */
4646 {
4647 /* We build this decl with vtbl_ptr_type_node, which is a
4648 `vtable_entry_type*'. It might seem more precise to use
4649 `vtable_entry_type (*)[N]' where N is the number of virtual
4650 functions. However, that would require the vtable pointer in
4651 base classes to have a different type than the vtable pointer
4652 in derived classes. We could make that happen, but that
4653 still wouldn't solve all the problems. In particular, the
4654 type-based alias analysis code would decide that assignments
4655 to the base class vtable pointer can't alias assignments to
4656 the derived class vtable pointer, since they have different
4657 types. Thus, in a derived class destructor, where the base
4658 class constructor was inlined, we could generate bad code for
4659 setting up the vtable pointer.
4661 Therefore, we use one type for all vtable pointers. We still
4662 use a type-correct type; it's just doesn't indicate the array
4663 bounds. That's better than using `void*' or some such; it's
4664 cleaner, and it let's the alias analysis code know that these
4665 stores cannot alias stores to void*! */
4666 tree field;
4679 /* This class is non-empty. */
4683 }
4686 }
4688 /* Add OFFSET to all base types of BINFO which is a base in the
4689 hierarchy dominated by T.
4691 OFFSET, which is a type offset, is number of bytes. */
4693 static void
4695 {
4697 tree primary_binfo;
4698 tree base_binfo;
4700 /* Update BINFO's offset. */
4705 offset));
4707 /* Find the primary base class. */
4713 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4714 downwards. */
4716 {
4717 /* Don't do the primary base twice. */
4725 }
4726 }
4728 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4729 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4730 empty subobjects of T. */
4732 static void
4734 {
4735 tree vbase;
4744 {
4745 /* In G++ 3.2, we incorrectly rounded the size before laying out
4746 the virtual bases. */
4748 #ifdef STRUCTURE_SIZE_BOUNDARY
4749 /* Packed structures don't need to have minimum size. */
4752 #endif
4756 }
4758 /* Find the last field. The artificial fields created for virtual
4759 bases will go after the last extant field to date. */
4764 /* Go through the virtual bases, allocating space for each virtual
4765 base that is not already a primary base class. These are
4766 allocated in inheritance graph order. */
4768 {
4773 {
4776 /* This virtual base is not a primary base of any class in the
4777 hierarchy, so we have to add space for it. */
4781 /* If the first virtual base might have been placed at a
4782 lower address, had we started from CLASSTYPE_SIZE, rather
4783 than TYPE_SIZE, issue a warning. There can be both false
4784 positives and false negatives from this warning in rare
4785 cases; to deal with all the possibilities would probably
4786 require performing both layout algorithms and comparing
4787 the results which is not particularly tractable. */
4789 && first_vbase
4790 && (tree_int_cst_lt
4795 bitsize_unit_node),
4798 "offset of virtual base %qT is not ABI-compliant and "
4800 basetype);
4803 }
4804 }
4805 }
4807 /* Returns the offset of the byte just past the end of the base class
4808 BINFO. */
4810 static tree
4812 {
4813 tree size;
4818 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4819 allocate some space for it. It cannot have virtual bases, so
4820 TYPE_SIZE_UNIT is fine. */
4822 else
4826 }
4828 /* Returns the offset of the byte just past the end of the base class
4829 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4830 only non-virtual bases are included. */
4832 static tree
4834 {
4837 tree binfo;
4838 tree base_binfo;
4839 tree offset;
4844 {
4854 }
4856 /* G++ 3.2 did not check indirect virtual bases. */
4860 {
4864 }
4867 }
4869 /* Warn about bases of T that are inaccessible because they are
4870 ambiguous. For example:
4872 struct S {};
4873 struct T : public S {};
4874 struct U : public S, public T {};
4876 Here, `(S*) new U' is not allowed because there are two `S'
4877 subobjects of U. */
4879 static void
4881 {
4884 tree basetype;
4885 tree binfo;
4886 tree base_binfo;
4888 /* If there are no repeated bases, nothing can be ambiguous. */
4892 /* Check direct bases. */
4895 {
4901 }
4903 /* Check for ambiguous virtual bases. */
4907 {
4913 }
4914 }
4916 /* Compare two INTEGER_CSTs K1 and K2. */
4918 static int
4920 {
4922 }
4924 /* Increase the size indicated in RLI to account for empty classes
4925 that are "off the end" of the class. */
4927 static void
4929 {
4930 tree eoc;
4931 tree rli_size;
4933 /* It might be the case that we grew the class to allocate a
4934 zero-sized base class. That won't be reflected in RLI, yet,
4935 because we are willing to overlay multiple bases at the same
4936 offset. However, now we need to make sure that RLI is big enough
4937 to reflect the entire class. */
4943 {
4945 /* In version 1 of the ABI, the size of a class that ends with
4946 a bitfield was not rounded up to a whole multiple of a
4947 byte. Because rli_size_unit_so_far returns only the number
4948 of fully allocated bytes, any extra bits were not included
4949 in the size. */
4951 else
4952 /* The size should have been rounded to a whole byte. */
4955 rli->bitpos
4964 }
4965 }
4967 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
4968 BINFO_OFFSETs for all of the base-classes. Position the vtable
4969 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
4971 static void
4973 {
4974 tree non_static_data_members;
4975 tree field;
4976 tree vptr;
4977 record_layout_info rli;
4978 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4979 types that appear at that offset. */
4980 splay_tree empty_base_offsets;
4981 /* True if the last field layed out was a bit-field. */
4983 /* The location at which the next field should be inserted. */
4985 /* T, as a base class. */
4986 tree base_t;
4988 /* Keep track of the first non-static data member. */
4991 /* Start laying out the record. */
4994 /* Mark all the primary bases in the hierarchy. */
4997 /* Create a pointer to our virtual function table. */
5000 /* The vptr is always the first thing in the class. */
5002 {
5007 }
5008 else
5011 /* Build FIELD_DECLs for all of the non-virtual base-types. */
5016 /* Layout the non-static data members. */
5018 {
5019 tree type;
5020 tree padding;
5022 /* We still pass things that aren't non-static data members to
5023 the back end, in case it wants to do something with them. */
5025 {
5027 /* If the static data member has incomplete type, keep track
5028 of it so that it can be completed later. (The handling
5029 of pending statics in finish_record_layout is
5030 insufficient; consider:
5032 struct S1;
5033 struct S2 { static S1 s1; };
5035 At this point, finish_record_layout will be called, but
5036 S1 is still incomplete.) */
5038 {
5040 /* The visibility of static data members is determined
5041 at their point of declaration, not their point of
5042 definition. */
5044 }
5046 }
5054 /* If this field is a bit-field whose width is greater than its
5055 type, then there are some special rules for allocating
5056 it. */
5059 {
5061 tree integer_type;
5063 /* We must allocate the bits as if suitably aligned for the
5064 longest integer type that fits in this many bits. type
5065 of the field. Then, we are supposed to use the left over
5066 bits as additional padding. */
5075 /* ITK now indicates a type that is too large for the
5076 field. We have to back up by one to find the largest
5077 type that fits. */
5078 do
5079 {
5084 /* Figure out how much additional padding is required. GCC
5085 3.2 always created a padding field, even if it had zero
5086 width. */
5089 {
5091 /* In a union, the padding field must have the full width
5092 of the bit-field; all fields start at offset zero. */
5094 else
5095 {
5098 "ABI-compliant and may change in a future "
5100 t);
5103 }
5104 }
5105 #ifdef PCC_BITFIELD_TYPE_MATTERS
5106 /* An unnamed bitfield does not normally affect the
5107 alignment of the containing class on a target where
5108 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
5109 make any exceptions for unnamed bitfields when the
5110 bitfields are longer than their types. Therefore, we
5111 temporarily give the field a name. */
5113 {
5116 }
5117 #endif
5122 empty_base_offsets);
5125 /* Now that layout has been performed, set the size of the
5126 field to the size of its declared type; the rest of the
5127 field is effectively invisible. */
5129 /* We must also reset the DECL_MODE of the field. */
5134 /* Versions of G++ before G++ 3.4 did not reset the
5135 DECL_MODE. */
5137 "the offset of %qD may not be ABI-compliant and may "
5139 }
5140 else
5142 empty_base_offsets);
5144 /* Remember the location of any empty classes in FIELD. */
5148 empty_base_offsets,
5151 /* If a bit-field does not immediately follow another bit-field,
5152 and yet it starts in the middle of a byte, we have failed to
5153 comply with the ABI. */
5156 /* The TREE_NO_WARNING flag gets set by Objective-C when
5157 laying out an Objective-C class. The ObjC ABI differs
5158 from the C++ ABI, and so we do not want a warning
5159 here. */
5161 && !last_field_was_bitfield
5164 bitsize_unit_node)))
5168 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
5169 offset of the field. */
5176 "classes to be placed at different locations in a "
5179 /* The middle end uses the type of expressions to determine the
5180 possible range of expression values. In order to optimize
5181 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
5182 must be made aware of the width of "i", via its type.
5184 Because C++ does not have integer types of arbitrary width,
5185 we must (for the purposes of the front end) convert from the
5186 type assigned here to the declared type of the bitfield
5187 whenever a bitfield expression is used as an rvalue.
5188 Similarly, when assigning a value to a bitfield, the value
5189 must be converted to the type given the bitfield here. */
5191 {
5196 {
5203 }
5204 }
5206 /* If we needed additional padding after this field, add it
5207 now. */
5209 {
5210 tree padding_field;
5213 FIELD_DECL,
5214 NULL_TREE,
5215 char_type_node);
5222 NULL_TREE,
5223 empty_base_offsets);
5224 }
5227 }
5230 {
5231 /* Make sure that we are on a byte boundary so that the size of
5232 the class without virtual bases will always be a round number
5233 of bytes. */
5236 }
5238 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5239 padding. */
5243 /* Delete all zero-width bit-fields from the list of fields. Now
5244 that the type is laid out they are no longer important. */
5247 /* Create the version of T used for virtual bases. We do not use
5248 make_class_type for this version; this is an artificial type. For
5249 a POD type, we just reuse T. */
5251 {
5254 /* Set the size and alignment for the new type. In G++ 3.2, all
5255 empty classes were considered to have size zero when used as
5256 base classes. */
5258 {
5263 "layout of classes derived from empty class %qT "
5265 t);
5266 }
5267 else
5268 {
5269 tree eoc;
5271 /* If the ABI version is not at least two, and the last
5272 field was a bit-field, RLI may not be on a byte
5273 boundary. In particular, rli_size_unit_so_far might
5274 indicate the last complete byte, while rli_size_so_far
5275 indicates the total number of bits used. Therefore,
5276 rli_size_so_far, rather than rli_size_unit_so_far, is
5277 used to compute TYPE_SIZE_UNIT. */
5285 eoc);
5292 }
5296 /* Copy the fields from T. */
5300 {
5302 FIELD_DECL,
5312 }
5314 /* Record the base version of the type. */
5317 }
5318 else
5321 /* Every empty class contains an empty class. */
5325 /* Set the TYPE_DECL for this type to contain the right
5326 value for DECL_OFFSET, so that we can use it as part
5327 of a COMPONENT_REF for multiple inheritance. */
5330 /* Now fix up any virtual base class types that we left lying
5331 around. We must get these done before we try to lay out the
5332 virtual function table. As a side-effect, this will remove the
5333 base subobject fields. */
5336 /* Make sure that empty classes are reflected in RLI at this
5337 point. */
5340 /* Make sure not to create any structures with zero size. */
5346 /* If this is a non-POD, declaring it packed makes a difference to how it
5347 can be used as a field; don't let finalize_record_size undo it. */
5351 /* Let the back end lay out the type. */
5354 /* Warn about bases that can't be talked about due to ambiguity. */
5357 /* Now that we're done with layout, give the base fields the real types. */
5362 /* Clean up. */
5369 }
5371 /* Determine the "key method" for the class type indicated by TYPE,
5372 and set CLASSTYPE_KEY_METHOD accordingly. */
5374 void
5376 {
5377 tree method;
5380 || processing_template_decl
5385 /* The key method is the first non-pure virtual function that is not
5386 inline at the point of class definition. On some targets the
5387 key function may not be inline; those targets should not call
5388 this function until the end of the translation unit. */
5394 {
5397 }
5400 }
5402 /* Perform processing required when the definition of T (a class type)
5403 is complete. */
5405 void
5407 {
5408 tree x;
5409 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5414 {
5419 }
5421 /* If this type was previously laid out as a forward reference,
5422 make sure we lay it out again. */
5426 /* Make assumptions about the class; we'll reset the flags if
5427 necessary. */
5432 /* Do end-of-class semantic processing: checking the validity of the
5433 bases and members and add implicitly generated methods. */
5436 /* Find the key method. */
5438 {
5439 /* The Itanium C++ ABI permits the key method to be chosen when
5440 the class is defined -- even though the key method so
5441 selected may later turn out to be an inline function. On
5442 some systems (such as ARM Symbian OS) the key method cannot
5443 be determined until the end of the translation unit. On such
5444 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5445 will cause the class to be added to KEYED_CLASSES. Then, in
5446 finish_file we will determine the key method. */
5450 /* If a polymorphic class has no key method, we may emit the vtable
5451 in every translation unit where the class definition appears. */
5454 }
5456 /* Layout the class itself. */
5459 /* We use the base type for trivial assignments, and hence it
5460 needs a mode. */
5465 /* If necessary, create the primary vtable for this class. */
5467 {
5468 /* We must enter these virtuals into the table. */
5472 /* Here we know enough to change the type of our virtual
5473 function table, but we will wait until later this function. */
5475 }
5478 {
5480 tree fn;
5487 /* Add entries for virtual functions introduced by this class. */
5491 /* Set DECL_VINDEX for all functions declared in this class. */
5493 fn;
5495 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5497 {
5501 /* A thunk. We should never be calling this entry directly
5502 from this vtable -- we'd use the entry for the non
5503 thunk base function. */
5507 }
5508 }
5512 /* Complete the rtl for any static member objects of the type we're
5513 working on. */
5520 /* Done with FIELDS...now decide whether to sort these for
5521 faster lookups later.
5523 We use a small number because most searches fail (succeeding
5524 ultimately as the search bores through the inheritance
5525 hierarchy), and we want this failure to occur quickly. */
5529 {
5535 field_decl_cmp);
5537 }
5539 /* Complain if one of the field types requires lower visibility. */
5542 /* Make the rtl for any new vtables we have created, and unmark
5543 the base types we marked. */
5546 /* Build the VTT for T. */
5549 /* This warning does not make sense for Java classes, since they
5550 cannot have destructors. */
5552 {
5553 tree dtor;
5557 if it were virtual, we would have created it by now. */
5558 !dtor
5567 "%q#T has virtual functions and accessible"
5569 }
5576 /* Class layout, assignment of virtual table slots, etc., is now
5577 complete. Give the back end a chance to tweak the visibility of
5578 the class or perform any other required target modifications. */
5585 /* Finish debugging output for this type. */
5587 }
5589 /* When T was built up, the member declarations were added in reverse
5590 order. Rearrange them to declaration order. */
5592 void
5594 {
5595 tree next;
5596 tree prev;
5597 tree x;
5599 /* The following lists are all in reverse order. Put them in
5600 declaration order now. */
5604 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5605 reverse order, so we can't just use nreverse. */
5610 {
5614 }
5616 {
5620 }
5621 }
5623 tree
5625 {
5628 /* Now that we've got all the field declarations, reverse everything
5629 as necessary. */
5634 /* Nadger the current location so that diagnostics point to the start of
5635 the struct, not the end. */
5639 {
5640 tree x;
5646 /* We need to emit an error message if this type was used as a parameter
5647 and it is an abstract type, even if it is a template. We construct
5648 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5649 account and we call complete_vars with this type, which will check
5650 the PARM_DECLS. Note that while the type is being defined,
5651 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5652 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5659 /* Remember current #pragma pack value. */
5661 }
5662 else
5671 else
5678 }
5679 \f
5680 /* Return the dynamic type of INSTANCE, if known.
5681 Used to determine whether the virtual function table is needed
5682 or not.
5684 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5685 of our knowledge of its type. *NONNULL should be initialized
5686 before this function is called. */
5688 static tree
5690 {
5691 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5694 {
5698 else
5702 /* This is a call to a constructor, hence it's never zero. */
5704 {
5708 }
5712 /* This is a call to a constructor, hence it's never zero. */
5714 {
5718 }
5727 /* Propagate nonnull. */
5732 CASE_CONVERT:
5738 {
5739 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5740 with a real object -- given &p->f, p can still be null. */
5742 /* ??? Probably should check DECL_WEAK here. */
5745 }
5749 /* If this component is really a base class reference, then the field
5750 itself isn't definitive. */
5759 {
5763 }
5764 /* fall through... */
5769 {
5773 }
5775 {
5779 /* if we're in a ctor or dtor, we know our type. */
5783 {
5787 }
5788 }
5790 {
5791 /* We only need one hash table because it is always left empty. */
5795 htab_hash_pointer,
5796 htab_eq_pointer,
5799 /* Reference variables should be references to objects. */
5803 /* Enter the INSTANCE in a table to prevent recursion; a
5804 variable's initializer may refer to the variable
5805 itself. */
5809 {
5810 tree type;
5819 }
5820 }
5825 }
5826 #undef RECUR
5827 }
5829 /* Return nonzero if the dynamic type of INSTANCE is known, and
5830 equivalent to the static type. We also handle the case where
5831 INSTANCE is really a pointer. Return negative if this is a
5832 ctor/dtor. There the dynamic type is known, but this might not be
5833 the most derived base of the original object, and hence virtual
5834 bases may not be layed out according to this type.
5836 Used to determine whether the virtual function table is needed
5837 or not.
5839 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5840 of our knowledge of its type. *NONNULL should be initialized
5841 before this function is called. */
5843 int
5845 {
5856 }
5858 \f
5859 void
5861 {
5864 current_class_stack
5872 }
5874 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5876 static void
5878 {
5879 tree type;
5881 /* We are re-entering the same class we just left, so we don't
5882 have to search the whole inheritance matrix to find all the
5883 decls to bind again. Instead, we install the cached
5884 class_shadowed list and walk through it binding names. */
5887 /* Restore IDENTIFIER_TYPE_VALUE. */
5889 type;
5892 }
5894 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5895 appropriate for TYPE.
5897 So that we may avoid calls to lookup_name, we cache the _TYPE
5898 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5900 For multiple inheritance, we perform a two-pass depth-first search
5901 of the type lattice. */
5903 void
5905 {
5906 class_stack_node_t csn;
5910 /* Make sure there is enough room for the new entry on the stack. */
5912 {
5914 current_class_stack
5916 current_class_stack_size);
5917 }
5919 /* Insert a new entry on the class stack. */
5926 current_class_depth++;
5928 /* Now set up the new type. */
5934 /* By default, things in classes are private, while things in
5935 structures or unions are public. */
5937 ? access_private_node
5943 {
5944 /* Forcibly remove any old class remnants. */
5946 }
5952 else
5954 }
5956 /* When we exit a toplevel class scope, we save its binding level so
5957 that we can restore it quickly. Here, we've entered some other
5958 class, so we must invalidate our cache. */
5960 void
5962 {
5964 }
5966 /* Get out of the current class scope. If we were in a class scope
5967 previously, that is the one popped to. */
5969 void
5971 {
5974 current_class_depth--;
5980 }
5982 /* Mark the top of the class stack as hidden. */
5984 void
5986 {
5989 }
5991 /* Mark the top of the class stack as un-hidden. */
5993 void
5995 {
5998 }
6000 /* Returns 1 if the class type currently being defined is either T or
6001 a nested type of T. */
6003 bool
6005 {
6013 /* We start looking from 1 because entry 0 is from global scope,
6014 and has no type. */
6016 {
6017 tree c;
6020 else
6021 {
6025 }
6030 }
6032 }
6034 /* If either current_class_type or one of its enclosing classes are derived
6035 from T, return the appropriate type. Used to determine how we found
6036 something via unqualified lookup. */
6038 tree
6040 {
6043 /* The bases of a dependent type are unknown. */
6054 {
6059 }
6062 }
6064 /* Returns the innermost class type which is not a lambda closure type. */
6066 tree
6068 {
6071 /* We start looking from 1 because entry 0 is from global scope,
6072 and has no type. */
6074 {
6075 tree c;
6078 else
6079 {
6083 }
6088 }
6090 }
6092 /* When entering a class scope, all enclosing class scopes' names with
6093 static meaning (static variables, static functions, types and
6094 enumerators) have to be visible. This recursive function calls
6095 pushclass for all enclosing class contexts until global or a local
6096 scope is reached. TYPE is the enclosed class. */
6098 void
6100 {
6101 /* A namespace might be passed in error cases, like A::B:C. */
6109 }
6111 /* Undoes a push_nested_class call. */
6113 void
6115 {
6121 }
6123 /* Returns the number of extern "LANG" blocks we are nested within. */
6125 int
6127 {
6129 }
6131 /* Set global variables CURRENT_LANG_NAME to appropriate value
6132 so that behavior of name-mangling machinery is correct. */
6134 void
6136 {
6140 {
6142 }
6144 {
6146 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
6147 (See record_builtin_java_type in decl.c.) However, that causes
6148 incorrect debug entries if these types are actually used.
6149 So we re-enable debug output after extern "Java". */
6158 }
6160 {
6162 }
6163 else
6165 }
6167 /* Get out of the current language scope. */
6169 void
6171 {
6173 }
6174 \f
6175 /* Type instantiation routines. */
6177 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
6178 matches the TARGET_TYPE. If there is no satisfactory match, return
6179 error_mark_node, and issue an error & warning messages under
6180 control of FLAGS. Permit pointers to member function if FLAGS
6181 permits. If TEMPLATE_ONLY, the name of the overloaded function was
6182 a template-id, and EXPLICIT_TARGS are the explicitly provided
6183 template arguments.
6185 If OVERLOAD is for one or more member functions, then ACCESS_PATH
6186 is the base path used to reference those member functions. If
6187 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
6188 resolved to a member function, access checks will be performed and
6189 errors issued if appropriate. */
6191 static tree
6193 tree overload,
6194 tsubst_flags_t flags,
6196 tree explicit_targs,
6197 tree access_path)
6198 {
6199 /* Here's what the standard says:
6201 [over.over]
6203 If the name is a function template, template argument deduction
6204 is done, and if the argument deduction succeeds, the deduced
6205 arguments are used to generate a single template function, which
6206 is added to the set of overloaded functions considered.
6208 Non-member functions and static member functions match targets of
6209 type "pointer-to-function" or "reference-to-function." Nonstatic
6210 member functions match targets of type "pointer-to-member
6211 function;" the function type of the pointer to member is used to
6212 select the member function from the set of overloaded member
6213 functions. If a nonstatic member function is selected, the
6214 reference to the overloaded function name is required to have the
6215 form of a pointer to member as described in 5.3.1.
6217 If more than one function is selected, any template functions in
6218 the set are eliminated if the set also contains a non-template
6219 function, and any given template function is eliminated if the
6220 set contains a second template function that is more specialized
6221 than the first according to the partial ordering rules 14.5.5.2.
6222 After such eliminations, if any, there shall remain exactly one
6223 selected function. */
6227 /* We store the matches in a TREE_LIST rooted here. The functions
6228 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
6229 interoperability with most_specialized_instantiation. */
6231 tree fn;
6232 tree target_fn_type;
6238 /* By the time we get here, we should be seeing only real
6239 pointer-to-member types, not the internal POINTER_TYPE to
6240 METHOD_TYPE representation unless it is in an IFUNC member
6241 function. */
6248 /* Check that the TARGET_TYPE is reasonable. */
6252 /* This is OK, too. */
6255 /* This is OK, too. This comes from a conversion to reference
6256 type. */
6260 else
6261 {
6267 }
6269 /* Non-member functions and static member functions match targets of type
6270 "pointer-to-function" or "reference-to-function." Nonstatic member
6271 functions match targets of type "pointer-to-member-function;" the
6272 function type of the pointer to member is used to select the member
6273 function from the set of overloaded member functions.
6275 So figure out the FUNCTION_TYPE that we want to match against. */
6278 /* If we can find a non-template function that matches, we can just
6279 use it. There's no point in generating template instantiations
6280 if we're just going to throw them out anyhow. But, of course, we
6281 can only do this when we don't *need* a template function. */
6283 {
6284 tree fns;
6287 {
6291 /* We're not looking for templates just yet. */
6296 /* We're looking for a non-static member, and this isn't
6297 one, or vice versa. */
6300 /* Ignore functions which haven't been explicitly
6301 declared. */
6305 /* See if there's a match. */
6308 }
6309 }
6311 /* Now, if we've already got a match (or matches), there's no need
6312 to proceed to the template functions. But, if we don't have a
6313 match we need to look at them, too. */
6315 {
6316 tree target_arg_types;
6317 tree target_ret_type;
6318 tree fns;
6321 tree arg;
6335 {
6337 tree instantiation;
6338 tree targs;
6341 /* We're only looking for templates. */
6346 /* We're not looking for a non-static member, and this is
6347 one, or vice versa. */
6350 /* Try to do argument deduction. */
6354 LOOKUP_NORMAL))
6355 /* Argument deduction failed. */
6358 /* Instantiate the template. */
6361 /* Instantiation failed. */
6364 /* See if there's a match. */
6367 }
6369 /* Now, remove all but the most specialized of the matches. */
6371 {
6376 NULL_TREE,
6377 NULL_TREE);
6378 }
6379 }
6381 /* Now we should have exactly one function in MATCHES. */
6383 {
6384 /* There were *no* matches. */
6386 {
6389 target_type);
6391 /* print_candidates expects a chain with the functions in
6392 TREE_VALUE slots, so we cons one up here (we're losing anyway,
6393 so why be clever?). */
6396 matches);
6399 }
6401 }
6403 {
6404 /* There were too many matches. First check if they're all
6405 the same function. */
6406 tree match;
6414 {
6416 {
6419 target_type);
6421 /* Since print_candidates expects the functions in the
6422 TREE_VALUE slot, we flip them here. */
6427 }
6430 }
6431 }
6433 /* Good, exactly one match. Now, convert it to the correct type. */
6438 {
6446 {
6449 }
6450 }
6452 /* If we're doing overload resolution purely for the purpose of
6453 determining conversion sequences, we should not consider the
6454 function used. If this conversion sequence is selected, the
6455 function will be marked as used at this point. */
6457 {
6458 /* Make =delete work with SFINAE. */
6463 }
6465 /* We could not check access to member functions when this
6466 expression was originally created since we did not know at that
6467 time to which function the expression referred. */
6470 {
6473 }
6479 else
6480 {
6481 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
6482 will mark the function as addressed, but here we must do it
6483 explicitly. */
6487 }
6488 }
6490 /* This function will instantiate the type of the expression given in
6491 RHS to match the type of LHSTYPE. If errors exist, then return
6492 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6493 we complain on errors. If we are not complaining, never modify rhs,
6494 as overload resolution wants to try many possible instantiations, in
6495 the hope that at least one will work.
6497 For non-recursive calls, LHSTYPE should be a function, pointer to
6498 function, or a pointer to member function. */
6500 tree
6502 {
6509 {
6513 }
6516 {
6522 /* Microsoft allows `A::f' to be resolved to a
6523 pointer-to-member. */
6524 ;
6525 else
6526 {
6531 }
6532 }
6535 {
6538 }
6540 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6541 deduce any type information. */
6543 {
6547 }
6549 /* There only a few kinds of expressions that may have a type
6550 dependent on overload resolution. */
6556 /* This should really only be used when attempting to distinguish
6557 what sort of a pointer to function we have. For now, any
6558 arithmetic operation which is not supported on pointers
6559 is rejected as an error. */
6562 {
6564 {
6570 /* Do not lose object's side effects. */
6574 }
6581 /* This can happen if we are forming a pointer-to-member for a
6582 member template. */
6585 /* Fall through. */
6588 {
6592 return
6596 }
6600 return
6604 access_path);
6607 {
6612 }
6619 }
6621 }
6622 \f
6623 /* Return the name of the virtual function pointer field
6624 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6625 this may have to look back through base types to find the
6626 ultimate field name. (For single inheritance, these could
6627 all be the same name. Who knows for multiple inheritance). */
6629 static tree
6631 {
6638 {
6644 }
6652 }
6654 void
6656 {
6657 #ifdef GATHER_STATISTICS
6661 {
6666 }
6667 #endif
6668 }
6670 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6671 according to [class]:
6672 The class-name is also inserted
6673 into the scope of the class itself. For purposes of access checking,
6674 the inserted class name is treated as if it were a public member name. */
6676 void
6678 {
6681 tree saved_cas;
6696 }
6698 /* Returns 1 if TYPE contains only padding bytes. */
6700 int
6702 {
6709 /* In G++ 3.2, whether or not a class was empty was determined by
6710 looking at its size. */
6713 else
6715 }
6717 /* Returns true if TYPE contains an empty class. */
6719 static bool
6721 {
6725 {
6726 tree field;
6727 tree binfo;
6728 tree base_binfo;
6740 }
6744 }
6746 /* Returns true if TYPE contains no actual data, just various
6747 possible combinations of empty classes. */
6749 bool
6751 {
6755 {
6756 tree field;
6757 tree binfo;
6758 tree base_binfo;
6771 }
6775 }
6777 /* Note that NAME was looked up while the current class was being
6778 defined and that the result of that lookup was DECL. */
6780 void
6782 {
6783 splay_tree names_used;
6785 /* If we're not defining a class, there's nothing to do. */
6791 /* If there's already a binding for this NAME, then we don't have
6792 anything to worry about. */
6805 }
6807 /* Note that NAME was declared (as DECL) in the current class. Check
6808 to see that the declaration is valid. */
6810 void
6812 {
6813 splay_tree names_used;
6814 splay_tree_node n;
6816 /* Look to see if we ever used this name. */
6817 names_used
6824 {
6825 /* [basic.scope.class]
6827 A name N used in a class S shall refer to the same declaration
6828 in its context and when re-evaluated in the completed scope of
6829 S. */
6833 }
6834 }
6836 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6837 Secondary vtables are merged with primary vtables; this function
6838 will return the VAR_DECL for the primary vtable. */
6840 tree
6842 {
6843 tree decl;
6847 {
6850 }
6854 }
6857 /* Returns the binfo for the primary base of BINFO. If the resulting
6858 BINFO is a virtual base, and it is inherited elsewhere in the
6859 hierarchy, then the returned binfo might not be the primary base of
6860 BINFO in the complete object. Check BINFO_PRIMARY_P or
6861 BINFO_LOST_PRIMARY_P to be sure. */
6863 static tree
6865 {
6866 tree primary_base;
6873 }
6875 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6877 static int
6879 {
6883 }
6885 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6886 INDENT should be zero when called from the top level; it is
6887 incremented recursively. IGO indicates the next expected BINFO in
6888 inheritance graph ordering. */
6890 static tree
6893 tree binfo,
6894 tree igo,
6896 {
6898 tree base_binfo;
6906 {
6909 }
6924 {
6928 TFF_PLAIN_IDENTIFIER),
6930 }
6932 {
6935 }
6940 {
6944 {
6948 TFF_PLAIN_IDENTIFIER));
6949 }
6951 {
6955 TFF_PLAIN_IDENTIFIER));
6956 }
6958 {
6962 TFF_PLAIN_IDENTIFIER));
6963 }
6965 {
6969 TFF_PLAIN_IDENTIFIER));
6970 }
6974 }
6980 }
6982 /* Dump the BINFO hierarchy for T. */
6984 static void
6986 {
6998 }
7000 /* Debug interface to hierarchy dumping. */
7002 void
7004 {
7006 }
7008 static void
7010 {
7015 {
7018 }
7019 }
7021 static void
7023 {
7024 tree value;
7026 HOST_WIDE_INT elt;
7034 TFF_PLAIN_IDENTIFIER));
7041 }
7043 static void
7045 {
7053 {
7060 {
7064 }
7068 }
7071 }
7073 static void
7075 {
7083 {
7088 }
7091 }
7093 /* Dump a function or thunk and its thunkees. */
7095 static void
7097 {
7100 tree thunks;
7108 {
7118 else
7124 }
7128 }
7130 /* Dump the thunks for FN. */
7132 void
7134 {
7136 }
7138 /* Virtual function table initialization. */
7140 /* Create all the necessary vtables for T and its base classes. */
7142 static void
7144 {
7145 tree vbase;
7149 /* We lay out the primary and secondary vtables in one contiguous
7150 vtable. The primary vtable is first, followed by the non-virtual
7151 secondary vtables in inheritance graph order. */
7155 /* Then come the virtual bases, also in inheritance graph order. */
7157 {
7161 }
7165 }
7167 /* Initialize the vtable for BINFO with the INITS. */
7169 static void
7171 {
7172 tree decl;
7178 }
7180 /* Build the VTT (virtual table table) for T.
7181 A class requires a VTT if it has virtual bases.
7183 This holds
7184 1 - primary virtual pointer for complete object T
7185 2 - secondary VTTs for each direct non-virtual base of T which requires a
7186 VTT
7187 3 - secondary virtual pointers for each direct or indirect base of T which
7188 has virtual bases or is reachable via a virtual path from T.
7189 4 - secondary VTTs for each direct or indirect virtual base of T.
7191 Secondary VTTs look like complete object VTTs without part 4. */
7193 static void
7195 {
7196 tree type;
7197 tree vtt;
7198 tree index;
7201 /* Build up the initializers for the VTT. */
7206 /* If we didn't need a VTT, we're done. */
7210 /* Figure out the type of the VTT. */
7214 /* Now, build the VTT object itself. */
7217 /* Add the VTT to the vtables list. */
7222 }
7224 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
7225 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7226 and CHAIN the vtable pointer for this binfo after construction is
7227 complete. VALUE can also be another BINFO, in which case we recurse. */
7229 static tree
7231 {
7232 tree vt;
7235 {
7241 else
7243 }
7246 }
7248 /* Data for secondary VTT initialization. */
7250 {
7251 /* Is this the primary VTT? */
7254 /* Current index into the VTT. */
7255 tree index;
7257 /* Vector of initializers built up. */
7260 /* The type being constructed by this secondary VTT. */
7261 tree type_being_constructed;
7264 /* Recursively build the VTT-initializer for BINFO (which is in the
7265 hierarchy dominated by T). INITS points to the end of the initializer
7266 list to date. INDEX is the VTT index where the next element will be
7267 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7268 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7269 for virtual bases of T. When it is not so, we build the constructor
7270 vtables for the BINFO-in-T variant. */
7272 static void
7274 {
7276 tree b;
7277 tree init;
7278 secondary_vptr_vtt_init_data data;
7281 /* We only need VTTs for subobjects with virtual bases. */
7285 /* We need to use a construction vtable if this is not the primary
7286 VTT. */
7288 {
7291 /* Record the offset in the VTT where this sub-VTT can be found. */
7293 }
7295 /* Add the address of the primary vtable for the complete object. */
7299 {
7302 }
7305 /* Recursively add the secondary VTTs for non-virtual bases. */
7310 /* Add secondary virtual pointers for all subobjects of BINFO with
7311 either virtual bases or reachable along a virtual path, except
7312 subobjects that are non-virtual primary bases. */
7322 /* data.inits might have grown as we added secondary virtual pointers.
7323 Make sure our caller knows about the new vector. */
7327 /* Add the secondary VTTs for virtual bases in inheritance graph
7328 order. */
7330 {
7335 }
7336 else
7337 /* Remove the ctor vtables we created. */
7339 }
7341 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7342 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7344 static tree
7346 {
7349 /* We don't care about bases that don't have vtables. */
7353 /* We're only interested in proper subobjects of the type being
7354 constructed. */
7358 /* We're only interested in bases with virtual bases or reachable
7359 via a virtual path from the type being constructed. */
7364 /* We're not interested in non-virtual primary bases. */
7368 /* Record the index where this secondary vptr can be found. */
7370 {
7375 {
7376 /* It's a primary virtual base, and this is not a
7377 construction vtable. Find the base this is primary of in
7378 the inheritance graph, and use that base's vtable
7379 now. */
7382 }
7383 }
7385 /* Add the initializer for the secondary vptr itself. */
7388 /* Advance the vtt index. */
7393 }
7395 /* Called from build_vtt_inits via dfs_walk. After building
7396 constructor vtables and generating the sub-vtt from them, we need
7397 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7398 binfo of the base whose sub vtt was generated. */
7400 static tree
7402 {
7406 /* If this class has no vtable, none of its bases do. */
7410 /* This might be a primary base, so have no vtable in this
7411 hierarchy. */
7414 /* If we scribbled the construction vtable vptr into BINFO, clear it
7415 out now. */
7421 }
7423 /* Build the construction vtable group for BINFO which is in the
7424 hierarchy dominated by T. */
7426 static void
7428 {
7429 tree type;
7430 tree vtbl;
7431 tree id;
7432 tree vbase;
7435 /* See if we've already created this construction vtable group. */
7441 /* Build a version of VTBL (with the wrong type) for use in
7442 constructing the addresses of secondary vtables in the
7443 construction vtable group. */
7451 /* Add the vtables for each of our virtual bases using the vbase in T
7452 binfo. */
7454 vbase;
7456 {
7457 tree b;
7464 }
7466 /* Figure out the type of the construction vtable. */
7474 /* Initialize the construction vtable. */
7478 }
7480 /* Add the vtbl initializers for BINFO (and its bases other than
7481 non-virtual primaries) to the list of INITS. BINFO is in the
7482 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7483 the constructor the vtbl inits should be accumulated for. (If this
7484 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7485 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7486 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7487 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7488 but are not necessarily the same in terms of layout. */
7490 static void
7492 tree orig_binfo,
7493 tree rtti_binfo,
7494 tree vtbl,
7495 tree t,
7497 {
7499 tree base_binfo;
7504 /* If it doesn't have a vptr, we don't do anything. */
7508 /* If we're building a construction vtable, we're not interested in
7509 subobjects that don't require construction vtables. */
7515 /* Build the initializers for the BINFO-in-T vtable. */
7518 /* Walk the BINFO and its bases. We walk in preorder so that as we
7519 initialize each vtable we can figure out at what offset the
7520 secondary vtable lies from the primary vtable. We can't use
7521 dfs_walk here because we need to iterate through bases of BINFO
7522 and RTTI_BINFO simultaneously. */
7524 {
7525 /* Skip virtual bases. */
7531 inits);
7532 }
7533 }
7535 /* Called from accumulate_vtbl_inits. Adds the initializers for the
7536 BINFO vtable to L. */
7538 static void
7540 tree orig_binfo,
7541 tree rtti_binfo,
7542 tree orig_vtbl,
7543 tree t,
7545 {
7552 {
7553 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7554 primary virtual base. If it is not the same primary in
7555 the hierarchy of T, we'll need to generate a ctor vtable
7556 for it, to place at its location in T. If it is the same
7557 primary, we still need a VTT entry for the vtable, but it
7558 should point to the ctor vtable for the base it is a
7559 primary for within the sub-hierarchy of RTTI_BINFO.
7561 There are three possible cases:
7563 1) We are in the same place.
7564 2) We are a primary base within a lost primary virtual base of
7565 RTTI_BINFO.
7566 3) We are primary to something not a base of RTTI_BINFO. */
7568 tree b;
7571 /* First, look through the bases we are primary to for RTTI_BINFO
7572 or a virtual base. */
7575 {
7580 }
7581 /* If we run out of primary links, keep looking down our
7582 inheritance chain; we might be an indirect primary. */
7586 found:
7588 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7589 base B and it is a base of RTTI_BINFO, this is case 2. In
7590 either case, we share our vtable with LAST, i.e. the
7591 derived-most base within B of which we are a primary. */
7594 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7595 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7596 binfo_ctor_vtable after everything's been set up. */
7599 /* Otherwise, this is case 3 and we get our own. */
7600 }
7607 {
7608 tree index;
7611 /* Add the initializer for this vtable. */
7615 /* Figure out the position to which the VPTR should point. */
7622 index);
7624 }
7627 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7628 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7629 straighten this out. */
7632 /* Throw away any unneeded intializers. */
7634 else
7635 /* For an ordinary vtable, set BINFO_VTABLE. */
7637 }
7641 /* Construct the initializer for BINFO's virtual function table. BINFO
7642 is part of the hierarchy dominated by T. If we're building a
7643 construction vtable, the ORIG_BINFO is the binfo we should use to
7644 find the actual function pointers to put in the vtable - but they
7645 can be overridden on the path to most-derived in the graph that
7646 ORIG_BINFO belongs. Otherwise,
7647 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7648 BINFO that should be indicated by the RTTI information in the
7649 vtable; it will be a base class of T, rather than T itself, if we
7650 are building a construction vtable.
7652 The value returned is a TREE_LIST suitable for wrapping in a
7653 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7654 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7655 number of non-function entries in the vtable.
7657 It might seem that this function should never be called with a
7658 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7659 base is always subsumed by a derived class vtable. However, when
7660 we are building construction vtables, we do build vtables for
7661 primary bases; we need these while the primary base is being
7662 constructed. */
7664 static void
7666 tree orig_binfo,
7667 tree t,
7668 tree rtti_binfo,
7671 {
7672 tree v;
7673 vtbl_init_data vid;
7675 tree vbinfo;
7679 /* Initialize VID. */
7687 /* The first vbase or vcall offset is at index -3 in the vtable. */
7690 /* Add entries to the vtable for RTTI. */
7693 /* Create an array for keeping track of the functions we've
7694 processed. When we see multiple functions with the same
7695 signature, we share the vcall offsets. */
7697 /* Add the vcall and vbase offset entries. */
7700 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7701 build_vbase_offset_vtbl_entries. */
7706 /* If the target requires padding between data entries, add that now. */
7708 {
7714 /* Move data entries into their new positions and add padding
7715 after the new positions. Iterate backwards so we don't
7716 overwrite entries that we would need to process later. */
7719 ix--)
7720 {
7728 {
7733 null_pointer_node);
7734 }
7735 }
7736 }
7741 /* The initializers for virtual functions were built up in reverse
7742 order. Straighten them out and add them to the running list in one
7743 step. */
7753 /* Go through all the ordinary virtual functions, building up
7754 initializers. */
7756 {
7757 tree delta;
7758 tree vcall_index;
7765 {
7769 {
7772 }
7774 }
7776 /* If the only definition of this function signature along our
7777 primary base chain is from a lost primary, this vtable slot will
7778 never be used, so just zero it out. This is important to avoid
7779 requiring extra thunks which cannot be generated with the function.
7781 We first check this in update_vtable_entry_for_fn, so we handle
7782 restored primary bases properly; we also need to do it here so we
7783 zero out unused slots in ctor vtables, rather than filling them
7784 with erroneous values (though harmless, apart from relocation
7785 costs). */
7790 {
7791 /* Pull the offset for `this', and the function to call, out of
7792 the list. */
7799 /* You can't call an abstract virtual function; it's abstract.
7800 So, we replace these functions with __pure_virtual. */
7802 {
7807 }
7808 else
7809 {
7811 {
7815 }
7816 /* Take the address of the function, considering it to be of an
7817 appropriate generic type. */
7819 }
7820 }
7822 /* And add it to the chain of initializers. */
7824 {
7829 else
7831 {
7838 }
7839 }
7840 else
7842 }
7843 }
7845 /* Adds to vid->inits the initializers for the vbase and vcall
7846 offsets in BINFO, which is in the hierarchy dominated by T. */
7848 static void
7850 {
7851 tree b;
7853 /* If this is a derived class, we must first create entries
7854 corresponding to the primary base class. */
7859 /* Add the vbase entries for this base. */
7861 /* Add the vcall entries for this base. */
7863 }
7865 /* Returns the initializers for the vbase offset entries in the vtable
7866 for BINFO (which is part of the class hierarchy dominated by T), in
7867 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7868 where the next vbase offset will go. */
7870 static void
7872 {
7873 tree vbase;
7874 tree t;
7875 tree non_primary_binfo;
7877 /* If there are no virtual baseclasses, then there is nothing to
7878 do. */
7884 /* We might be a primary base class. Go up the inheritance hierarchy
7885 until we find the most derived class of which we are a primary base:
7886 it is the offset of that which we need to use. */
7889 {
7890 tree b;
7892 /* If we have reached a virtual base, then it must be a primary
7893 base (possibly multi-level) of vid->binfo, or we wouldn't
7894 have called build_vcall_and_vbase_vtbl_entries for it. But it
7895 might be a lost primary, so just skip down to vid->binfo. */
7897 {
7900 }
7906 }
7908 /* Go through the virtual bases, adding the offsets. */
7910 vbase;
7912 {
7913 tree b;
7914 tree delta;
7919 /* Find the instance of this virtual base in the complete
7920 object. */
7923 /* If we've already got an offset for this virtual base, we
7924 don't need another one. */
7929 /* Figure out where we can find this vbase offset. */
7938 /* The vbase offset had better be the same. */
7941 /* The next vbase will come at a more negative offset. */
7945 /* The initializer is the delta from BINFO to this virtual base.
7946 The vbase offsets go in reverse inheritance-graph order, and
7947 we are walking in inheritance graph order so these end up in
7948 the right order. */
7955 }
7956 }
7958 /* Adds the initializers for the vcall offset entries in the vtable
7959 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7960 to VID->INITS. */
7962 static void
7964 {
7965 /* We only need these entries if this base is a virtual base. We
7966 compute the indices -- but do not add to the vtable -- when
7967 building the main vtable for a class. */
7970 /* If BINFO is RTTI_BINFO, then (since BINFO does not
7971 correspond to VID->DERIVED), we are building a primary
7972 construction virtual table. Since this is a primary
7973 virtual table, we do not need the vcall offsets for
7974 BINFO. */
7976 {
7977 /* We need a vcall offset for each of the virtual functions in this
7978 vtable. For example:
7980 class A { virtual void f (); };
7981 class B1 : virtual public A { virtual void f (); };
7982 class B2 : virtual public A { virtual void f (); };
7983 class C: public B1, public B2 { virtual void f (); };
7985 A C object has a primary base of B1, which has a primary base of A. A
7986 C also has a secondary base of B2, which no longer has a primary base
7987 of A. So the B2-in-C construction vtable needs a secondary vtable for
7988 A, which will adjust the A* to a B2* to call f. We have no way of
7989 knowing what (or even whether) this offset will be when we define B2,
7990 so we store this "vcall offset" in the A sub-vtable and look it up in
7991 a "virtual thunk" for B2::f.
7993 We need entries for all the functions in our primary vtable and
7994 in our non-virtual bases' secondary vtables. */
7996 /* If we are just computing the vcall indices -- but do not need
7997 the actual entries -- not that. */
8000 /* Now, walk through the non-virtual bases, adding vcall offsets. */
8002 }
8003 }
8005 /* Build vcall offsets, starting with those for BINFO. */
8007 static void
8009 {
8011 tree primary_binfo;
8012 tree base_binfo;
8014 /* Don't walk into virtual bases -- except, of course, for the
8015 virtual base for which we are building vcall offsets. Any
8016 primary virtual base will have already had its offsets generated
8017 through the recursion in build_vcall_and_vbase_vtbl_entries. */
8021 /* If BINFO has a primary base, process it first. */
8026 /* Add BINFO itself to the list. */
8029 /* Scan the non-primary bases of BINFO. */
8033 }
8035 /* Called from build_vcall_offset_vtbl_entries_r. */
8037 static void
8039 {
8040 /* Make entries for the rest of the virtuals. */
8042 {
8043 tree orig_fn;
8045 /* The ABI requires that the methods be processed in declaration
8046 order. G++ 3.2 used the order in the vtable. */
8048 orig_fn;
8052 }
8053 else
8054 {
8055 tree derived_virtuals;
8056 tree base_virtuals;
8057 tree orig_virtuals;
8058 /* If BINFO is a primary base, the most derived class which has
8059 BINFO as a primary base; otherwise, just BINFO. */
8060 tree non_primary_binfo;
8062 /* We might be a primary base class. Go up the inheritance hierarchy
8063 until we find the most derived class of which we are a primary base:
8064 it is the BINFO_VIRTUALS there that we need to consider. */
8067 {
8068 tree b;
8070 /* If we have reached a virtual base, then it must be vid->vbase,
8071 because we ignore other virtual bases in
8072 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
8073 base (possibly multi-level) of vid->binfo, or we wouldn't
8074 have called build_vcall_and_vbase_vtbl_entries for it. But it
8075 might be a lost primary, so just skip down to vid->binfo. */
8077 {
8081 }
8087 }
8090 /* For a ctor vtable we need the equivalent binfo within the hierarchy
8091 where rtti_binfo is the most derived type. */
8092 non_primary_binfo
8098 base_virtuals;
8102 {
8103 tree orig_fn;
8105 /* Find the declaration that originally caused this function to
8106 be present in BINFO_TYPE (binfo). */
8109 /* When processing BINFO, we only want to generate vcall slots for
8110 function slots introduced in BINFO. So don't try to generate
8111 one if the function isn't even defined in BINFO. */
8116 }
8117 }
8118 }
8120 /* Add a vcall offset entry for ORIG_FN to the vtable. */
8122 static void
8124 {
8126 tree vcall_offset;
8127 tree derived_entry;
8129 /* If there is already an entry for a function with the same
8130 signature as FN, then we do not need a second vcall offset.
8131 Check the list of functions already present in the derived
8132 class vtable. */
8134 {
8136 /* We only use one vcall offset for virtual destructors,
8137 even though there are two virtual table entries. */
8141 }
8143 /* If we are building these vcall offsets as part of building
8144 the vtable for the most derived class, remember the vcall
8145 offset. */
8147 {
8150 NULL);
8153 }
8155 /* The next vcall offset will be found at a more negative
8156 offset. */
8160 /* Keep track of this function. */
8164 {
8165 tree base;
8166 tree fn;
8168 /* Find the overriding function. */
8172 integer_zero_node);
8173 else
8174 {
8177 /* The vbase we're working on is a primary base of
8178 vid->binfo. But it might be a lost primary, so its
8179 BINFO_OFFSET might be wrong, so we just use the
8180 BINFO_OFFSET from vid->binfo. */
8186 vcall_offset);
8187 }
8188 /* Add the initializer to the vtable. */
8190 }
8191 }
8193 /* Return vtbl initializers for the RTTI entries corresponding to the
8194 BINFO's vtable. The RTTI entries should indicate the object given
8195 by VID->rtti_binfo. */
8197 static void
8199 {
8200 tree b;
8201 tree t;
8202 tree offset;
8203 tree decl;
8204 tree init;
8208 /* To find the complete object, we will first convert to our most
8209 primary base, and then add the offset in the vtbl to that value. */
8213 {
8214 tree primary_base;
8220 }
8224 /* The second entry is the address of the typeinfo object. */
8227 else
8230 /* Convert the declaration to a type that can be stored in the
8231 vtable. */
8235 /* Add the offset-to-top entry. It comes earlier in the vtable than
8236 the typeinfo entry. Convert the offset to look like a
8237 function pointer, so that we can put it in the vtable. */
8240 }
8242 /* Fold a OBJ_TYPE_REF expression to the address of a function.
8243 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
8245 tree
8247 {
8251 tree fndecl;
8254 {
8255 i += (TARGET_VTABLE_USES_DESCRIPTORS
8258 }
8262 #ifdef ENABLE_CHECKING
8265 #endif
8270 }